1
00:00:00,000 --> 00:00:03,600


2
00:00:03,600 --> 00:00:05,650
DAVID J. MALAN: [SPEAKING SPANISH]

3
00:00:05,650 --> 00:00:17,470


4
00:00:17,470 --> 00:00:20,680
I'd like to speak more
English here on out.

5
00:00:20,680 --> 00:00:26,760
Those of you who have taken CS50
online or watched some of the videos

6
00:00:26,760 --> 00:00:29,860
know that I typically speak very fast
like this in English, which is what

7
00:00:29,860 --> 00:00:32,409
Spanish currently sounds like to me.

8
00:00:32,409 --> 00:00:35,650
So I will do my best to speak
more slowly, so that those

9
00:00:35,650 --> 00:00:38,720
of you with headsets can follow along.

10
00:00:38,720 --> 00:00:44,140
So this is a talk and a story
about CS50 at scale and [SPANISH]..

11
00:00:44,140 --> 00:00:47,470
And what I mean by this is
that this map here represents

12
00:00:47,470 --> 00:00:50,710
where this course CS50 now exists.

13
00:00:50,710 --> 00:00:55,760
In red are dots where we have
high schools taking or teaching

14
00:00:55,760 --> 00:00:57,610
CS50 in some form.

15
00:00:57,610 --> 00:01:01,180
And in blue are dots where we
have universities as well as

16
00:01:01,180 --> 00:01:03,290
of last year alone.

17
00:01:03,290 --> 00:01:07,670
And so CS50 at scale for
us means a big question.

18
00:01:07,670 --> 00:01:12,670
How do we go about bringing computer
science to students beyond Cambridge?

19
00:01:12,670 --> 00:01:17,110
And how do we go about supporting
students as well as teachers here

20
00:01:17,110 --> 00:01:21,880
in Nicaragua, elsewhere in the United
States, and really around the world?

21
00:01:21,880 --> 00:01:23,800
But before we do that,
I thought I would give

22
00:01:23,800 --> 00:01:28,690
those of you who are unfamiliar
with CS50 a glimpse of what it is.

23
00:01:28,690 --> 00:01:32,140
At the end of the day, CS50
is Harvard's introduction

24
00:01:32,140 --> 00:01:35,410
to the intellectual
enterprises of computer science

25
00:01:35,410 --> 00:01:36,700
and the art of programming.

26
00:01:36,700 --> 00:01:38,980
It's an introduction
to computer science.

27
00:01:38,980 --> 00:01:44,410
And the syllabus, the material we
teach, I daresay, is fairly common

28
00:01:44,410 --> 00:01:46,020
and is fairly traditional.

29
00:01:46,020 --> 00:01:49,540
But what is very
untraditional about CS50

30
00:01:49,540 --> 00:01:55,300
is how we approach the course's culture,
how we approach the course's community,

31
00:01:55,300 --> 00:02:01,540
and where we emphasize students'
experience beyond the material alone.

32
00:02:01,540 --> 00:02:04,450
And so this means in
addition to teaching students

33
00:02:04,450 --> 00:02:09,940
computer science and, in turn, how to
program, there is this whole experience

34
00:02:09,940 --> 00:02:13,300
that students have in
Cambridge, in New Haven,

35
00:02:13,300 --> 00:02:18,700
here now in Managua, and beyond
that involves puzzle days and CS50

36
00:02:18,700 --> 00:02:23,620
hackathons and CS50 fairs, as well
as the office hours and sections

37
00:02:23,620 --> 00:02:26,140
and lectures wherein
they learn that material.

38
00:02:26,140 --> 00:02:29,440
And if you've not yet taken
CS50 or are considering

39
00:02:29,440 --> 00:02:32,170
doing so here with our
friends Carlos and Sylvio

40
00:02:32,170 --> 00:02:34,490
and all of the teaching
fellows already here,

41
00:02:34,490 --> 00:02:37,150
I thought I'd give you a glimpse
at what this experience can

42
00:02:37,150 --> 00:02:41,804
be like through the lens
of Harvard University.

43
00:02:41,804 --> 00:02:42,470
[VIDEO PLAYBACK]

44
00:02:42,470 --> 00:02:46,278
[MUSIC PLAYING]

45
00:02:46,278 --> 00:02:49,134


46
00:02:49,134 --> 00:02:52,962
- All right, this is CS50!

47
00:02:52,962 --> 00:02:56,946
- [SINGING] [INAUDIBLE]

48
00:02:56,946 --> 00:04:12,642


49
00:04:12,642 --> 00:04:14,634
[INAUDIBLE]

50
00:04:14,634 --> 00:04:18,618
- [SINGING] [INAUDIBLE]

51
00:04:18,618 --> 00:05:05,928


52
00:05:05,928 --> 00:05:12,402
- This is, boom, CS50!

53
00:05:12,402 --> 00:05:13,050
[END PLAYBACK]

54
00:05:13,050 --> 00:05:15,800
DAVID J. MALAN: If you don't
recognize him, that's--

55
00:05:15,800 --> 00:05:16,469
sure.

56
00:05:16,469 --> 00:05:22,566
[APPLAUSE]

57
00:05:22,566 --> 00:05:25,320
That video is thanks
to CS50's production

58
00:05:25,320 --> 00:05:27,660
team, who's expert in video back home.

59
00:05:27,660 --> 00:05:30,300
And if you don't recognize him,
that man was Steve Ballmer,

60
00:05:30,300 --> 00:05:35,130
the former CEO of Microsoft, who joined
us two years ago for a guest lecture.

61
00:05:35,130 --> 00:05:38,230
So I've been teaching
CS50 for 10 years now.

62
00:05:38,230 --> 00:05:41,580
And I've been alive for
40, apparently, now.

63
00:05:41,580 --> 00:05:45,510
And over those 10 years when
I inherited the course, one

64
00:05:45,510 --> 00:05:48,330
of the most important
things to do, for me,

65
00:05:48,330 --> 00:05:51,750
was to ensure that the
course was accessible.

66
00:05:51,750 --> 00:05:55,890
The course itself and CS50
computer science more generally,

67
00:05:55,890 --> 00:06:01,040
I daresay, had a reputation
of being a field to beware.

68
00:06:01,040 --> 00:06:02,040
Let's see if this.

69
00:06:02,040 --> 00:06:05,040


70
00:06:05,040 --> 00:06:07,610
Well, that didn't fix it.

71
00:06:07,610 --> 00:06:08,140
There we go.

72
00:06:08,140 --> 00:06:09,400
A field to beware.

73
00:06:09,400 --> 00:06:13,090
And what I didn't want to do when
taking over this course was simply

74
00:06:13,090 --> 00:06:16,210
make it easier or
remove material from it,

75
00:06:16,210 --> 00:06:20,440
but rather to maintain the course's
historical rigor and the course's

76
00:06:20,440 --> 00:06:25,870
historical workload, but to nonetheless
make it more fun, more applicable,

77
00:06:25,870 --> 00:06:29,450
and to take what had previously been
an on ramp that might look like this,

78
00:06:29,450 --> 00:06:31,660
where we assume this much
material at the beginning,

79
00:06:31,660 --> 00:06:35,440
and to lower the entry point
for students without experience,

80
00:06:35,440 --> 00:06:37,450
those students less
comfortable, but still

81
00:06:37,450 --> 00:06:40,840
ensuring that the end of just
as successful and just as

82
00:06:40,840 --> 00:06:44,680
learned as students who had
even studied the class before.

83
00:06:44,680 --> 00:06:48,490
And since then have we applied this
same idea really all around the world.

84
00:06:48,490 --> 00:06:53,710
In 2007 is, again, when I took over
CS50 in Cambridge, Massachusetts.

85
00:06:53,710 --> 00:06:58,090
In 2012 did the course become
freely available on edX.

86
00:06:58,090 --> 00:07:01,030
If unfamiliar, this is
a free platform online

87
00:07:01,030 --> 00:07:03,580
that you can take courses
on for free and engage

88
00:07:03,580 --> 00:07:05,140
with students around the world.

89
00:07:05,140 --> 00:07:09,430
And the course even since 2007
had been freely available as what

90
00:07:09,430 --> 00:07:11,500
MIT has called open courseware.

91
00:07:11,500 --> 00:07:14,120
All of the handouts, all of
the videos, all of the problem

92
00:07:14,120 --> 00:07:16,420
sets, everything was freely available.

93
00:07:16,420 --> 00:07:19,510
But via edX now did we have an
even larger community of students

94
00:07:19,510 --> 00:07:22,240
who were discovering computer
science by way of our course

95
00:07:22,240 --> 00:07:26,170
and other courses from MIT
and UC Berkeley and elsewhere.

96
00:07:26,170 --> 00:07:29,790
And then in 2015 we introduced
another version of the class.

97
00:07:29,790 --> 00:07:32,980
It's very common after
university for some students

98
00:07:32,980 --> 00:07:35,680
to go to graduate school, for
instance, in business studies

99
00:07:35,680 --> 00:07:38,440
and receive an MBA,
a degree in business.

100
00:07:38,440 --> 00:07:41,710
And we adapted CS50 to
that particular audience.

101
00:07:41,710 --> 00:07:44,950
So there's a shorter version,
a different version of CS50

102
00:07:44,950 --> 00:07:49,180
that focuses on how you use technology
to solve problems in business

103
00:07:49,180 --> 00:07:52,000
and how you go about thinking
about cloud computing

104
00:07:52,000 --> 00:07:54,350
and security and the cost thereof.

105
00:07:54,350 --> 00:07:59,290
So whereas CS50 itself here in Managua
and in Cambridge and Yale is very much

106
00:07:59,290 --> 00:08:03,160
bottom-up-- you learn by doing and you
build things and you struggle through

107
00:08:03,160 --> 00:08:04,540
the building of those things--

108
00:08:04,540 --> 00:08:08,050
the MBA class is more of a top-down
discussion-oriented class where

109
00:08:08,050 --> 00:08:12,340
you don't get your hands as dirty with
programming, but you talk about topics

110
00:08:12,340 --> 00:08:16,225
and you better understand who
the engineers you will work with,

111
00:08:16,225 --> 00:08:17,920
how they tend to operate.

112
00:08:17,920 --> 00:08:22,780
In 2015 we also transitioned the
class to Yale, another big university

113
00:08:22,780 --> 00:08:24,070
in the United States.

114
00:08:24,070 --> 00:08:28,860
And then in 2015 did we also
roll out what we call CS50 AP.

115
00:08:28,860 --> 00:08:32,559
AP means advanced placement, which
is a common program in some schools.

116
00:08:32,559 --> 00:08:37,270
And it's an opportunity for us to adapt
the course to a high school audience.

117
00:08:37,270 --> 00:08:40,809
Similarly, not changing
expectations, not making it easier,

118
00:08:40,809 --> 00:08:43,480
not making it lighter,
but with that demographic,

119
00:08:43,480 --> 00:08:45,490
allowing students more time.

120
00:08:45,490 --> 00:08:50,270
Whereas at Harvard and Yale, we might
typically have a 12-week semester,

121
00:08:50,270 --> 00:08:53,510
so you have only 12 weeks to do all
of the work, at the high school level,

122
00:08:53,510 --> 00:08:56,140
they typically have as many as 36 weeks.

123
00:08:56,140 --> 00:08:57,440
But it's the same work.

124
00:08:57,440 --> 00:08:58,680
It's the same tools.

125
00:08:58,680 --> 00:09:00,190
It's the same experience.

126
00:09:00,190 --> 00:09:03,610
But it ensures that students,
even without experience,

127
00:09:03,610 --> 00:09:05,970
can be successful in the end.

128
00:09:05,970 --> 00:09:08,740
And in terms of some numbers,
if curious, at Harvard

129
00:09:08,740 --> 00:09:11,320
we happen to be the
largest course these days.

130
00:09:11,320 --> 00:09:14,920
With undergraduates and graduate
students about 700 students

131
00:09:14,920 --> 00:09:16,630
each semester in the fall.

132
00:09:16,630 --> 00:09:20,352
We have about 150 students
at Yale and then 300 students

133
00:09:20,352 --> 00:09:22,060
through Harvard's
Extension School, which

134
00:09:22,060 --> 00:09:25,000
is continuing education,
a program for adults

135
00:09:25,000 --> 00:09:28,300
or for students who aren't
in university themselves.

136
00:09:28,300 --> 00:09:32,800
At the MBA program we have 100
students or so each semester.

137
00:09:32,800 --> 00:09:35,980
And with CS50x it's a lot of people.

138
00:09:35,980 --> 00:09:37,720
Not all of them engage actively.

139
00:09:37,720 --> 00:09:39,500
They might sign up and come and go.

140
00:09:39,500 --> 00:09:42,010
But it's over 1 million
registrants these days have

141
00:09:42,010 --> 00:09:43,810
found the course via edX.

142
00:09:43,810 --> 00:09:47,830
And we now have, most excitingly, not
just students all around the world,

143
00:09:47,830 --> 00:09:49,150
but support structures.

144
00:09:49,150 --> 00:09:51,940
Much what like Sylvio
and Carlos are doing here

145
00:09:51,940 --> 00:09:57,320
do we have in Bolivia and Miami and
Rhode Island and St. Louis in the US--

146
00:09:57,320 --> 00:09:58,660
Bolivia not being in the US--

147
00:09:58,660 --> 00:10:02,230
Kansas City in the US, Burma,
Chile, Netherlands, Nicaragua now,

148
00:10:02,230 --> 00:10:06,740
of course, the UK, and
Ukraine, and beyond.

149
00:10:06,740 --> 00:10:10,330
And so these are just some of the
folks that you saw depicted graphically

150
00:10:10,330 --> 00:10:12,590
with the map just a little bit ago.

151
00:10:12,590 --> 00:10:15,130
And then in CS50 AP
this coming year will we

152
00:10:15,130 --> 00:10:20,040
likely have as many as 300 teachers,
300 high schools or [SPANISH]

153
00:10:20,040 --> 00:10:25,130
teaching CS50 in some form with
over 6,000 students as well.

154
00:10:25,130 --> 00:10:28,720
So what is CS50, particularly
if you've not yet experienced it

155
00:10:28,720 --> 00:10:31,360
through the opportunity here or online?

156
00:10:31,360 --> 00:10:34,300
So this is what Sanders
Theater looks like at Harvard.

157
00:10:34,300 --> 00:10:37,960
We're fortunate to have such a beautiful
space to fit all of these students.

158
00:10:37,960 --> 00:10:41,320
And it's here that Scully and
Ramon and our production team

159
00:10:41,320 --> 00:10:44,320
back home actually captures
the course's material.

160
00:10:44,320 --> 00:10:46,150
We don't just shoot the lectures once.

161
00:10:46,150 --> 00:10:49,300
Every year we refresh the
course and bring in new topics

162
00:10:49,300 --> 00:10:52,540
and bring in new news that
might have happened in industry

163
00:10:52,540 --> 00:10:55,930
and ultimately create an
ongoing opportunity for students

164
00:10:55,930 --> 00:11:00,580
to learn conceptually what computer
science is and how to program.

165
00:11:00,580 --> 00:11:02,440
But there's a whole
support structure too.

166
00:11:02,440 --> 00:11:05,730
This is a glimpse of a space that
looks a little like Hogwarts,

167
00:11:05,730 --> 00:11:08,910
but is really a dining hall where
a lot of the first years eat.

168
00:11:08,910 --> 00:11:12,859
But also at night do we use spaces
like this to bring students together.

169
00:11:12,859 --> 00:11:14,400
And this, too, is a remarkable thing.

170
00:11:14,400 --> 00:11:19,080
As opposed to just having study halls
or fairly traditional classrooms,

171
00:11:19,080 --> 00:11:22,680
we actually bring students to
non-conventional places on campus,

172
00:11:22,680 --> 00:11:25,890
like the dining hall here,
or other places on campus

173
00:11:25,890 --> 00:11:28,320
where there might be food
and there might be friends.

174
00:11:28,320 --> 00:11:31,320
But the goal, really, is to
have students rubbing shoulders

175
00:11:31,320 --> 00:11:34,650
with each other from different fields,
working on their computer science

176
00:11:34,650 --> 00:11:37,590
homework or some other
topic all together.

177
00:11:37,590 --> 00:11:41,490
And here is, if curious, our
friends at Yale down the road.

178
00:11:41,490 --> 00:11:43,890
But then in terms of the
communities, and this is really

179
00:11:43,890 --> 00:11:47,520
what's made CS50x scale so special,
these are some of our friends

180
00:11:47,520 --> 00:11:52,500
here in Miami Dade, one of whom
actually on the left here, Arturo Real,

181
00:11:52,500 --> 00:11:55,800
is from Venezuela and was
studying in Miami Dade

182
00:11:55,800 --> 00:11:58,380
College, a large school
in Florida in the US,

183
00:11:58,380 --> 00:12:02,100
and actually now works with us full-time
in Cambridge as a result of having

184
00:12:02,100 --> 00:12:04,947
finished his studies there
and taken CS50 in Miami.

185
00:12:04,947 --> 00:12:06,780
These are some of our
friends here in Chile.

186
00:12:06,780 --> 00:12:09,000
And if you're familiar,
you can see students, maybe

187
00:12:09,000 --> 00:12:12,420
like some of your own classmates,
implementing bubble sort

188
00:12:12,420 --> 00:12:13,750
there up front.

189
00:12:13,750 --> 00:12:15,820
These are some of our friends in London.

190
00:12:15,820 --> 00:12:17,520
Here we have Burma.

191
00:12:17,520 --> 00:12:19,230
Here we have friends in Bolivia.

192
00:12:19,230 --> 00:12:22,020
And then, of course, some
of our own friends here.

193
00:12:22,020 --> 00:12:24,570
So you might see yourself
up on the slide now as well.

194
00:12:24,570 --> 00:12:27,990
And in addition to these folks do we
have a whole community of teachers.

195
00:12:27,990 --> 00:12:30,660
This was one of our first
group of high school teachers

196
00:12:30,660 --> 00:12:34,350
that adopted or adapted CS50
for their own classroom.

197
00:12:34,350 --> 00:12:37,590
And this was our first
ever CS50 hackathon

198
00:12:37,590 --> 00:12:40,140
for high school students in New York.

199
00:12:40,140 --> 00:12:43,020
Eight schools-- four public
schools, four private schools--

200
00:12:43,020 --> 00:12:47,310
came together for a Saturday afternoon
to work on their problem sets,

201
00:12:47,310 --> 00:12:51,570
to work on their final projects,
but ultimately working together

202
00:12:51,570 --> 00:12:54,630
and experiencing together
a field that had otherwise

203
00:12:54,630 --> 00:12:56,796
been very unfamiliar to them.

204
00:12:56,796 --> 00:12:58,920
So what does it mean beyond
all of the photographs?

205
00:12:58,920 --> 00:13:02,370
And what is it-- especially if you're
considering computer science here

206
00:13:02,370 --> 00:13:04,560
or beyond, what is it
you actually learn?

207
00:13:04,560 --> 00:13:06,450
And what is it we actually do?

208
00:13:06,450 --> 00:13:11,370
So the syllabus itself is fairly
conventionally structured,

209
00:13:11,370 --> 00:13:13,170
but we cover quite a bit of material.

210
00:13:13,170 --> 00:13:20,190
Indeed, CS50 is what most schools would
call CS1 plus CS2 all combined together

211
00:13:20,190 --> 00:13:21,600
in just one semester.

212
00:13:21,600 --> 00:13:25,080
And so we begin the semester introducing
students first to programming

213
00:13:25,080 --> 00:13:30,360
and really computational thinking by
way of a problem set called Scratch

214
00:13:30,360 --> 00:13:34,410
and by way of ultimately a language
called C, which is more cryptic,

215
00:13:34,410 --> 00:13:37,770
which is more traditional, but is
a more powerful language still.

216
00:13:37,770 --> 00:13:42,240
And in that world do we explore
topics like arrays and algorithms

217
00:13:42,240 --> 00:13:44,730
and data structures
and memory management.

218
00:13:44,730 --> 00:13:49,170
And indeed, those of you taking CS50x
right now are roughly at this point,

219
00:13:49,170 --> 00:13:51,060
I believe, in the semester.

220
00:13:51,060 --> 00:13:52,860
And what then comes next?

221
00:13:52,860 --> 00:13:56,100
Well, we transition from that
to, really, web programming.

222
00:13:56,100 --> 00:14:00,000
More modern incarnations of
computer science and programming.

223
00:14:00,000 --> 00:14:04,440
Looking at HTTP and the web and
web programming, more generally,

224
00:14:04,440 --> 00:14:06,690
and also at topics
like machine learning.

225
00:14:06,690 --> 00:14:09,670
All the rage these days with
Uber and other companies

226
00:14:09,670 --> 00:14:12,510
is the idea of self-driving
cars and the implications

227
00:14:12,510 --> 00:14:14,651
of that and the technology behind that.

228
00:14:14,651 --> 00:14:17,400
And so did we introduce this topic,
thanks to our friends at Yale,

229
00:14:17,400 --> 00:14:19,000
for the very first time.

230
00:14:19,000 --> 00:14:22,440
And then at the end of the semester
do we move away from C altogether

231
00:14:22,440 --> 00:14:26,374
and introduce students to a bit
of Python and SQL and JavaScript.

232
00:14:26,374 --> 00:14:29,040
These are just different programming
languages, if not familiar.

233
00:14:29,040 --> 00:14:33,130
But the goal is so that when students
take a class like CS50 and exit it,

234
00:14:33,130 --> 00:14:37,710
they don't say, I learned C, one
specific programming language, rather,

235
00:14:37,710 --> 00:14:41,640
they say, I learned computer science,
but more specifically in programming,

236
00:14:41,640 --> 00:14:45,240
I learned how to program with
procedural or imperative languages,

237
00:14:45,240 --> 00:14:46,707
for those familiar.

238
00:14:46,707 --> 00:14:48,540
But what is the structure
of the class then?

239
00:14:48,540 --> 00:14:51,330
In Cambridge and at
Harvard and Yale it's

240
00:14:51,330 --> 00:14:54,420
12 weeks, though this is different
based on the various geographies

241
00:14:54,420 --> 00:14:56,040
and where students take the class.

242
00:14:56,040 --> 00:15:00,510
At Harvard there's eight homeworks or
nine homeworks, one exam, one quiz,

243
00:15:00,510 --> 00:15:03,630
and one final project, the last
of which is the most impactful.

244
00:15:03,630 --> 00:15:07,890
It's an opportunity for students,
without being told by us what to do,

245
00:15:07,890 --> 00:15:10,920
it's an opportunity for
them to design and implement

246
00:15:10,920 --> 00:15:13,110
a project of their very own.

247
00:15:13,110 --> 00:15:15,900
But it's really in terms of
the course's problem sets

248
00:15:15,900 --> 00:15:19,380
that students have the most
challenges and learn the most.

249
00:15:19,380 --> 00:15:22,020
It's one thing to just listen
to someone like me speak

250
00:15:22,020 --> 00:15:24,300
or even attend section or office hours.

251
00:15:24,300 --> 00:15:28,860
Most of students' time is spent
on these problem sets, [SPANISH]..

252
00:15:28,860 --> 00:15:33,690
And they cover very domain
inspired or specific problems.

253
00:15:33,690 --> 00:15:37,020
In Scratch, for instance, this is
a graphical programming language

254
00:15:37,020 --> 00:15:41,110
where you can drag and drop puzzle
pieces on the screen that lock together

255
00:15:41,110 --> 00:15:43,680
and then make characters
on the screen animate.

256
00:15:43,680 --> 00:15:46,545
In C then do we implement--

257
00:15:46,545 --> 00:15:48,420
if you're familiar with
Super Mario Brothers,

258
00:15:48,420 --> 00:15:50,550
a little something like
Super Mario Brothers

259
00:15:50,550 --> 00:15:54,300
Pyramid using a very simple language
with which most students are not yet

260
00:15:54,300 --> 00:15:55,230
familiar.

261
00:15:55,230 --> 00:15:58,560
But then we very quickly transition
to topics like cryptography.

262
00:15:58,560 --> 00:16:01,734
And those who might know,
what is cryptography?

263
00:16:01,734 --> 00:16:03,030
AUDIENCE: Hiding information?

264
00:16:03,030 --> 00:16:04,488
DAVID J. MALAN: Hiding information.

265
00:16:04,488 --> 00:16:07,570
So if you want to send a secret
message to a friend in class,

266
00:16:07,570 --> 00:16:09,820
you could just write it
in English or Spanish.

267
00:16:09,820 --> 00:16:12,550
But if the teacher intercepts
it, he or she, of course,

268
00:16:12,550 --> 00:16:14,240
will know what you're talking about.

269
00:16:14,240 --> 00:16:17,950
So maybe instead of doing that,
you change all of your letters.

270
00:16:17,950 --> 00:16:23,380
A becomes B, B becomes C, or something
more sophisticated than that.

271
00:16:23,380 --> 00:16:24,880
That might be encryption.

272
00:16:24,880 --> 00:16:26,490
Encoding the information in some way.

273
00:16:26,490 --> 00:16:28,960
So we have students for
this homework assignment

274
00:16:28,960 --> 00:16:34,202
actually implement a program that
encrypts and decrypts information.

275
00:16:34,202 --> 00:16:35,410
And for the more [INAUDIBLE].

276
00:16:35,410 --> 00:16:36,076
[VIDEO PLAYBACK]

277
00:16:36,076 --> 00:16:38,903
[MUSIC PLAYING]

278
00:16:38,903 --> 00:16:42,396
- [SINGING] [INAUDIBLE]

279
00:16:42,396 --> 00:18:21,198


280
00:18:21,198 --> 00:18:27,737
- This is, boom, CS50!

281
00:18:27,737 --> 00:18:28,320
[END PLAYBACK]

282
00:18:28,320 --> 00:18:31,070
DAVID J. MALAN: If you don't
recognize him, that's--

283
00:18:31,070 --> 00:18:32,212
sure.

284
00:18:32,212 --> 00:18:38,170
[APPLAUSE]

285
00:18:38,170 --> 00:18:40,630
That video is thanks
to CS50's production

286
00:18:40,630 --> 00:18:42,970
team, who's experts in video back home.

287
00:18:42,970 --> 00:18:45,610
And if you don't recognize him,
that man was Steve Ballmer,

288
00:18:45,610 --> 00:18:50,410
the former CEO of Microsoft, who joined
us two years ago for a guest lecture.

289
00:18:50,410 --> 00:18:53,500
So I've been teaching
CS50 for 10 years now.

290
00:18:53,500 --> 00:18:56,890
And I've been alive for
40, apparently, now.

291
00:18:56,890 --> 00:19:00,820
And over those 10 years when
I inherited the course, one

292
00:19:00,820 --> 00:19:03,640
of the most important
things to do, for me,

293
00:19:03,640 --> 00:19:07,030
was to ensure that the
course was accessible.

294
00:19:07,030 --> 00:19:11,170
The course itself and CS
computer science more generally,

295
00:19:11,170 --> 00:19:16,647
I daresay, had a reputation
of being a field to beware.

296
00:19:16,647 --> 00:19:20,056
Let's see if this.

297
00:19:20,056 --> 00:19:22,890
Well, that didn't fix it.

298
00:19:22,890 --> 00:19:23,430
There we go.

299
00:19:23,430 --> 00:19:24,690
A field to beware.

300
00:19:24,690 --> 00:19:28,380
And what I didn't want to do when
taking over this course was simply

301
00:19:28,380 --> 00:19:31,500
make it easier or
remove material from it,

302
00:19:31,500 --> 00:19:35,730
but rather to maintain the course's
historical rigor and the course's

303
00:19:35,730 --> 00:19:41,160
historical workload, but to nonetheless
make it more fun, more applicable,

304
00:19:41,160 --> 00:19:44,740
and to take what had previously been
an on ramp that might look like this,

305
00:19:44,740 --> 00:19:46,950
where we assume this much
material at the beginning,

306
00:19:46,950 --> 00:19:50,760
and to lower the entry point
for students without experience,

307
00:19:50,760 --> 00:19:52,740
those students less
comfortable, but still

308
00:19:52,740 --> 00:19:56,670
ensuring that they end up just
as successful and just as learned

309
00:19:56,670 --> 00:19:59,970
as students who had even
studied the class before.

310
00:19:59,970 --> 00:20:03,780
And since then have we applied this
same idea really all around the world.

311
00:20:03,780 --> 00:20:09,000
In 2007 is, again, when I took over
CS50 in Cambridge, Massachusetts.

312
00:20:09,000 --> 00:20:13,380
In 2012 did the course become
freely available on edX.

313
00:20:13,380 --> 00:20:16,320
If unfamiliar, this is
a free platform online

314
00:20:16,320 --> 00:20:18,900
that you can take courses
on for free and engage

315
00:20:18,900 --> 00:20:20,430
with students around the world.

316
00:20:20,430 --> 00:20:24,720
And the course even since 2007
had been freely available as what

317
00:20:24,720 --> 00:20:26,790
MIT has called open courseware.

318
00:20:26,790 --> 00:20:29,400
All of the handouts, all of
the videos, all of the problem

319
00:20:29,400 --> 00:20:31,710
sets, everything was freely available.

320
00:20:31,710 --> 00:20:34,830
But via edX now did we have an
even larger community of students

321
00:20:34,830 --> 00:20:37,530
who were discovering computer
science by way of our course

322
00:20:37,530 --> 00:20:41,460
and other courses from MIT
and UC Berkeley and elsewhere.

323
00:20:41,460 --> 00:20:45,090
And then in 2015 we introduced
another version of the class.

324
00:20:45,090 --> 00:20:48,270
It's very common after
university for some students

325
00:20:48,270 --> 00:20:50,970
to go to graduate school, for
instance, in business studies

326
00:20:50,970 --> 00:20:53,730
and receive an MBA,
a degree in business.

327
00:20:53,730 --> 00:20:57,000
And we adapted CS50 to
that particular audience.

328
00:20:57,000 --> 00:21:00,300
So there's a shorter version,
a different version of CS50

329
00:21:00,300 --> 00:21:04,470
that focuses on how you use technology
to solve problems in business

330
00:21:04,470 --> 00:21:07,290
and how you go about thinking
about cloud computing

331
00:21:07,290 --> 00:21:09,640
and security and the cost thereof.

332
00:21:09,640 --> 00:21:14,580
So whereas CS50 itself here in Managua
and in Cambridge and Yale is very much

333
00:21:14,580 --> 00:21:18,450
bottom-up-- you learn by doing and you
build things and you struggle through

334
00:21:18,450 --> 00:21:19,830
the building of those things--

335
00:21:19,830 --> 00:21:23,340
the MBA class is more of a top-down
discussion-oriented class where

336
00:21:23,340 --> 00:21:27,630
you don't get your hands dirty with
programming, but you talk about topics

337
00:21:27,630 --> 00:21:31,515
and you better understand who
the engineers you will work with,

338
00:21:31,515 --> 00:21:33,210
how they tend to operate.

339
00:21:33,210 --> 00:21:38,100
In 2015 we also transitioned the
class to Yale, another big university

340
00:21:38,100 --> 00:21:39,360
in the United States.

341
00:21:39,360 --> 00:21:44,160
And then in 2015 did we also
roll out what we call CS50 AP.

342
00:21:44,160 --> 00:21:47,850
AP means advanced placement, which
is a common program in some schools.

343
00:21:47,850 --> 00:21:52,560
And it's an opportunity for us to adapt
the course to a high school audience.

344
00:21:52,560 --> 00:21:56,100
Similarly, not changing
expectations, not making it easier,

345
00:21:56,100 --> 00:21:58,770
not making it lighter,
but with that demographic,

346
00:21:58,770 --> 00:22:00,780
allowing students more time.

347
00:22:00,780 --> 00:22:05,560
Whereas at Harvard and Yale, we might
typically have a 12-week semester.

348
00:22:05,560 --> 00:22:07,860
So you have only 12 weeks
to do all of the work.

349
00:22:07,860 --> 00:22:11,430
At the high school level, they
typically have as many as 36 weeks.

350
00:22:11,430 --> 00:22:12,730
But it's the same work.

351
00:22:12,730 --> 00:22:13,980
It's the same tools.

352
00:22:13,980 --> 00:22:15,480
It's the same experience.

353
00:22:15,480 --> 00:22:18,900
But it ensures that students
even without experience

354
00:22:18,900 --> 00:22:21,280
can be successful in the end.

355
00:22:21,280 --> 00:22:24,030
And in terms of some numbers,
if curious, at Harvard

356
00:22:24,030 --> 00:22:26,610
we happen to be the
largest course these days.

357
00:22:26,610 --> 00:22:30,210
With undergraduates and graduate
students about 700 students

358
00:22:30,210 --> 00:22:31,920
each semester in the fall.

359
00:22:31,920 --> 00:22:35,642
We have about 150 students
at Yale and then 300 students

360
00:22:35,642 --> 00:22:37,350
through Harvard's
Extension School, which

361
00:22:37,350 --> 00:22:40,290
is continuing education,
a program for adults

362
00:22:40,290 --> 00:22:43,260
or for students who aren't
in university themselves.

363
00:22:43,260 --> 00:22:48,090
At the MBA program we have 100
students or so each semester.

364
00:22:48,090 --> 00:22:51,270
And with CS50x it's a lot of people.

365
00:22:51,270 --> 00:22:53,010
Not all of them engage actively.

366
00:22:53,010 --> 00:22:54,790
They might sign up and come and go.

367
00:22:54,790 --> 00:22:57,330
But it's over 1 million
registrants these days have

368
00:22:57,330 --> 00:22:59,100
found the course via edX.

369
00:22:59,100 --> 00:23:03,120
And we now have, most excitingly, not
just students all around the world,

370
00:23:03,120 --> 00:23:04,440
but support structures.

371
00:23:04,440 --> 00:23:07,230
Much what like Sylvio
and Carlos are doing here

372
00:23:07,230 --> 00:23:12,620
do we have in Bolivia and Miami and
Rhode Island and St. Louis in the US--

373
00:23:12,620 --> 00:23:13,950
Bolivia not being in the US--

374
00:23:13,950 --> 00:23:17,520
Kansas City in the US, Burma,
Chile, Netherlands, Nicaragua now,

375
00:23:17,520 --> 00:23:22,030
of course, the UK, and
Ukraine, and beyond.

376
00:23:22,030 --> 00:23:25,620
And so these are just some of the
folks that you saw depicted graphically

377
00:23:25,620 --> 00:23:27,880
with the map just a little bit ago.

378
00:23:27,880 --> 00:23:30,420
And then in CS50 AP
this coming year will we

379
00:23:30,420 --> 00:23:35,340
likely have as many as 300 teachers,
300 high schools or [SPANISH]

380
00:23:35,340 --> 00:23:40,450
teaching CS50 in some form with
over 6,000 students as well.

381
00:23:40,450 --> 00:23:44,010
So what is CS50, particularly
if you've not yet experienced it

382
00:23:44,010 --> 00:23:46,680
through the opportunity here or online?

383
00:23:46,680 --> 00:23:49,620
So this is what Sanders
Theater looks like at Harvard.

384
00:23:49,620 --> 00:23:53,250
We're fortunate to have such a beautiful
space to fit all of these students.

385
00:23:53,250 --> 00:23:56,610
And it's here that Scully and
Ramon and our production team

386
00:23:56,610 --> 00:23:59,520
back home actually captures
the course's material.

387
00:23:59,520 --> 00:24:01,440
We don't just shoot the lectures once.

388
00:24:01,440 --> 00:24:04,590
Every year we refresh the
course and bring in new topics

389
00:24:04,590 --> 00:24:07,860
and bring in new news that
might have happened in industry

390
00:24:07,860 --> 00:24:11,220
and ultimately creates an
ongoing opportunity for students

391
00:24:11,220 --> 00:24:15,870
to learn conceptually what computer
science is and how to program.

392
00:24:15,870 --> 00:24:17,730
But there's a whole
support structure too.

393
00:24:17,730 --> 00:24:21,010
This is a glimpse of a space that
looks a little like Hogwarts,

394
00:24:21,010 --> 00:24:24,190
but is really a dining hall where
a lot of the first years eat.

395
00:24:24,190 --> 00:24:28,139
But also at nights do we use spaces
like this to bring students together.

396
00:24:28,139 --> 00:24:29,680
And this, too, is a remarkable thing.

397
00:24:29,680 --> 00:24:34,360
As opposed to just having study halls
or fairly traditional classrooms,

398
00:24:34,360 --> 00:24:37,960
we actually bring students to
non-conventional places on campus,

399
00:24:37,960 --> 00:24:41,200
like the dining hall here,
or other places on campus

400
00:24:41,200 --> 00:24:43,630
where there might be food
and there might be friends.

401
00:24:43,630 --> 00:24:46,630
But the goal, really, is to
have students rubbing shoulders

402
00:24:46,630 --> 00:24:49,960
with each other from different fields,
working on their computer science

403
00:24:49,960 --> 00:24:52,900
homework or some other topic altogether.

404
00:24:52,900 --> 00:24:56,770
And here is, if curious, our
friends at Yale down the road.

405
00:24:56,770 --> 00:24:59,170
But then in terms of the
communities, and this is really

406
00:24:59,170 --> 00:25:02,830
what's made CS50x scale so special,
these are some of our friends

407
00:25:02,830 --> 00:25:07,810
here in Miami Dade, one of whom
actually on the left here, Arturo Real,

408
00:25:07,810 --> 00:25:11,080
is from Venezuela and was
studying in Miami Dade

409
00:25:11,080 --> 00:25:13,690
College, a large school
in Florida in the US,

410
00:25:13,690 --> 00:25:17,410
and actually now works with us full-time
in Cambridge as a result of having

411
00:25:17,410 --> 00:25:20,257
finished his studies there
and taken CS50 in Miami.

412
00:25:20,257 --> 00:25:22,090
These are some of our
friends here in Chile.

413
00:25:22,090 --> 00:25:24,280
And if you're familiar,
you can see students, maybe

414
00:25:24,280 --> 00:25:27,690
like some of your own classmates,
implementing bubble sort

415
00:25:27,690 --> 00:25:29,030
there up front.

416
00:25:29,030 --> 00:25:31,120
These are some of our friends in London.

417
00:25:31,120 --> 00:25:32,800
Here we have Burma.

418
00:25:32,800 --> 00:25:34,540
Here we have friends in Bolivia.

419
00:25:34,540 --> 00:25:37,330
And then, of course, some
of our own friends here.

420
00:25:37,330 --> 00:25:39,850
So you might see yourself
up on the slide now as well.

421
00:25:39,850 --> 00:25:43,270
And in addition to these folks do we
have a whole community of teachers.

422
00:25:43,270 --> 00:25:45,940
This was one of our first
group of high school teachers

423
00:25:45,940 --> 00:25:49,660
that adopted or adapted CS50
for their own classroom.

424
00:25:49,660 --> 00:25:52,870
And this was our first
ever CS50 hackathon

425
00:25:52,870 --> 00:25:55,460
for high school students in New York.

426
00:25:55,460 --> 00:25:58,330
Eight schools-- four public
schools, four private schools--

427
00:25:58,330 --> 00:26:02,620
came together for a Saturday afternoon
to work on their problem sets,

428
00:26:02,620 --> 00:26:06,850
to work on their final projects,
but ultimately working together

429
00:26:06,850 --> 00:26:09,940
and experiencing together
a field that had otherwise

430
00:26:09,940 --> 00:26:12,075
been very unfamiliar to them.

431
00:26:12,075 --> 00:26:14,200
So what does it mean beyond
all of the photographs?

432
00:26:14,200 --> 00:26:17,650
And what is it-- especially if you're
considering computer science here

433
00:26:17,650 --> 00:26:19,840
or beyond, what is it
you actually learn?

434
00:26:19,840 --> 00:26:21,760
And what is that we actually do?

435
00:26:21,760 --> 00:26:26,680
So the syllabus itself is fairly
conventionally structured,

436
00:26:26,680 --> 00:26:28,450
but we cover quite a bit of material.

437
00:26:28,450 --> 00:26:35,500
Indeed, CS50 is what most schools would
call CS1 plus CS2 all combined together

438
00:26:35,500 --> 00:26:36,910
in just one semester.

439
00:26:36,910 --> 00:26:40,390
And so we begin the semester introducing
students first to programming

440
00:26:40,390 --> 00:26:45,640
and really computational thinking by
way of a problem set called Scratch

441
00:26:45,640 --> 00:26:49,720
and by way of ultimately a language
called C, which is more cryptic,

442
00:26:49,720 --> 00:26:53,080
which is more traditional, but is
a more powerful language still.

443
00:26:53,080 --> 00:26:57,520
And in that world do we explore
topics like arrays and algorithms

444
00:26:57,520 --> 00:27:00,010
and data structures
and memory management.

445
00:27:00,010 --> 00:27:04,480
And indeed, those of you taking CS50x
right now are roughly at this point,

446
00:27:04,480 --> 00:27:06,340
I believe, in the semester.

447
00:27:06,340 --> 00:27:08,240
And what comes next?

448
00:27:08,240 --> 00:27:11,390
Well, we transition from that
to, really, web programming.

449
00:27:11,390 --> 00:27:15,280
More modern incarnations of
computer science and programming.

450
00:27:15,280 --> 00:27:19,720
Looking at HTTP and the web and
web programming, more generally,

451
00:27:19,720 --> 00:27:22,000
and also at topics
like machine learning.

452
00:27:22,000 --> 00:27:24,950
All the rage these days with
Uber and other companies

453
00:27:24,950 --> 00:27:27,820
is the idea of self-driving
cars and the implications

454
00:27:27,820 --> 00:27:29,931
of that and the technology behind that.

455
00:27:29,931 --> 00:27:32,680
And so did we introduce this topic,
thanks to our friends at Yale,

456
00:27:32,680 --> 00:27:34,280
for the very first time.

457
00:27:34,280 --> 00:27:37,720
And then at the end of the semester
do we move away from C altogether

458
00:27:37,720 --> 00:27:41,654
and introduce students to a bit
of Python and SQL and JavaScript.

459
00:27:41,654 --> 00:27:44,320
These are just different programming
languages, if not familiar.

460
00:27:44,320 --> 00:27:48,410
But the goal is so that when students
take a class like CS50 and exit it,

461
00:27:48,410 --> 00:27:52,990
they don't say, I learned C, one
specific programming language, rather,

462
00:27:52,990 --> 00:27:56,920
they say, I learned computer science,
but more specifically in programming,

463
00:27:56,920 --> 00:28:00,550
I learned how to program with
procedural or imperative languages,

464
00:28:00,550 --> 00:28:01,987
for those familiar.

465
00:28:01,987 --> 00:28:03,820
But what is the structure
of the class then?

466
00:28:03,820 --> 00:28:06,610
In Cambridge and at
Harvard and Yale it's

467
00:28:06,610 --> 00:28:09,730
12 weeks, though this is different
based on the various geographies

468
00:28:09,730 --> 00:28:11,320
and where students take the class.

469
00:28:11,320 --> 00:28:15,790
At Harvard there's eight homeworks or
nine homeworks, one exam, one quiz,

470
00:28:15,790 --> 00:28:18,940
and one final project, the last
of which is the most impactful.

471
00:28:18,940 --> 00:28:23,170
It's an opportunity for students,
without being told by us what to do,

472
00:28:23,170 --> 00:28:26,200
it's an opportunity for
them to design and implement

473
00:28:26,200 --> 00:28:28,390
a project of their very own.

474
00:28:28,390 --> 00:28:31,210
But it's really in terms of
the course's problem sets

475
00:28:31,210 --> 00:28:34,690
that students have the most
challenges and learn the most.

476
00:28:34,690 --> 00:28:37,330
It's one thing to just listen
to someone like me speak

477
00:28:37,330 --> 00:28:39,610
or even attend section or office hours.

478
00:28:39,610 --> 00:28:44,170
Most of students' time is spent
on these problem sets, [SPANISH],,

479
00:28:44,170 --> 00:28:48,970
and they cover very domain
inspired or specific problems.

480
00:28:48,970 --> 00:28:52,300
In Scratch, for instance, this is
a graphical programming language

481
00:28:52,300 --> 00:28:56,390
where you can drag and drop puzzle
pieces on the screen that lock together

482
00:28:56,390 --> 00:28:58,990
and then make characters
on the screen animate.

483
00:28:58,990 --> 00:29:01,856
In C then do we implement--

484
00:29:01,856 --> 00:29:03,730
if you're familiar with
Super Mario Brothers,

485
00:29:03,730 --> 00:29:05,830
a little something like
Super Mario Brothers

486
00:29:05,830 --> 00:29:09,580
Pyramid using a very simple language
with which most students are not yet

487
00:29:09,580 --> 00:29:10,510
familiar.

488
00:29:10,510 --> 00:29:13,870
But then we very quickly transition
to topics like cryptography.

489
00:29:13,870 --> 00:29:17,006
And those who might know,
what is cryptography?

490
00:29:17,006 --> 00:29:18,290
AUDIENCE: Hiding information?

491
00:29:18,290 --> 00:29:19,748
DAVID J. MALAN: Hiding information.

492
00:29:19,748 --> 00:29:22,860
So if you want to send a secret
message to a friend in class,

493
00:29:22,860 --> 00:29:25,140
you could just write it
in English or Spanish.

494
00:29:25,140 --> 00:29:27,840
But if the teacher intercepts
it, he or she, of course,

495
00:29:27,840 --> 00:29:29,530
will know what you're talking about.

496
00:29:29,530 --> 00:29:33,270
So maybe instead of doing that,
you change all of your letters.

497
00:29:33,270 --> 00:29:38,670
A becomes B, B becomes C, or something
more sophisticated than that.

498
00:29:38,670 --> 00:29:41,780
That might be encryption, encoding
the information in some way.

499
00:29:41,780 --> 00:29:44,250
So we have students for
this homework assignment

500
00:29:44,250 --> 00:29:49,682
actually implement a program that
encrypts and decrypts information.

501
00:29:49,682 --> 00:29:52,890
And for the more comfortable students
in the class, and this is a key detail,

502
00:29:52,890 --> 00:29:56,130
too, we traditionally have
different tracks within the class.

503
00:29:56,130 --> 00:30:00,100
A track for students less comfortable,
and students more comfortable,

504
00:30:00,100 --> 00:30:02,220
and then students
somewhere in between, each

505
00:30:02,220 --> 00:30:06,090
of whom can decide whether to do
the less comfortable or the more

506
00:30:06,090 --> 00:30:10,050
comfortable homework assignments that
are equally weighted, just as important

507
00:30:10,050 --> 00:30:11,170
as each other.

508
00:30:11,170 --> 00:30:13,470
But in this case, too,
we might give students

509
00:30:13,470 --> 00:30:17,460
a bunch of passwords from an actual
computer system that are encrypted

510
00:30:17,460 --> 00:30:20,230
or technically hashed in some way.

511
00:30:20,230 --> 00:30:23,820
And they have to write software
that cracks those passwords,

512
00:30:23,820 --> 00:30:27,780
figures out what they are by writing
software that kind of guesses

513
00:30:27,780 --> 00:30:28,920
intelligently.

514
00:30:28,920 --> 00:30:30,900
Well, maybe it's a word in a dictionary.

515
00:30:30,900 --> 00:30:32,400
Maybe it's a birthdate.

516
00:30:32,400 --> 00:30:34,590
Maybe it's something that's very common.

517
00:30:34,590 --> 00:30:38,730
And the goal is to crack those
passwords as quickly as possible.

518
00:30:38,730 --> 00:30:39,620
Game of 15.

519
00:30:39,620 --> 00:30:43,770
We give students code for the very
first time, 100 or more lines of code,

520
00:30:43,770 --> 00:30:46,920
that they have to first read
and understand and then add to.

521
00:30:46,920 --> 00:30:49,930
So you're not only starting
with an empty window.

522
00:30:49,930 --> 00:30:50,670
Forensics.

523
00:30:50,670 --> 00:30:52,170
One of my favorite.

524
00:30:52,170 --> 00:30:55,710
Typically, we'll walk around
campus taking digital photos

525
00:30:55,710 --> 00:30:58,710
of people, places, or things.

526
00:30:58,710 --> 00:31:03,060
And then every year I accidentally
delete the photos from my phone

527
00:31:03,060 --> 00:31:04,260
or from my camera.

528
00:31:04,260 --> 00:31:08,010
And so we make what's called
a forensic image of the data.

529
00:31:08,010 --> 00:31:12,600
Just copy all of the 0's and 1's
off of the device and into a file,

530
00:31:12,600 --> 00:31:15,060
give students that
file, and then they have

531
00:31:15,060 --> 00:31:20,010
to write software to recover all
of the photographs from that file,

532
00:31:20,010 --> 00:31:23,920
hopefully recovering all of the
photographs that I, myself, lost.

533
00:31:23,920 --> 00:31:26,640
Thereafter do we implement misspellings.

534
00:31:26,640 --> 00:31:30,390
So here we challenge students
not just to write correct code,

535
00:31:30,390 --> 00:31:33,840
but to write good code, efficient
code that isn't necessarily

536
00:31:33,840 --> 00:31:38,010
theoretically good, but actually
good in terms of performance.

537
00:31:38,010 --> 00:31:42,270
We give students a big
file of 150,000 words--

538
00:31:42,270 --> 00:31:46,770
so a really big file-- and they have
to implement a spell checker but data

539
00:31:46,770 --> 00:31:50,280
structures underneath the
hood that implement a spell

540
00:31:50,280 --> 00:31:53,080
checker as quickly as possible.

541
00:31:53,080 --> 00:31:57,720
And we measure how much time they use
on the CPU, the brains of the computer,

542
00:31:57,720 --> 00:32:02,820
and we measure how much RAM or memory
they use to actually run their code.

543
00:32:02,820 --> 00:32:05,070
And then we have a
leaderboard a ranking,

544
00:32:05,070 --> 00:32:07,380
if students opt in,
where you can see how

545
00:32:07,380 --> 00:32:09,660
you're doing compared
to your friends in terms

546
00:32:09,660 --> 00:32:14,460
of minimizing just how much memory
and CPU time you might be using.

547
00:32:14,460 --> 00:32:19,530
And then lastly do we transition to web
programming and Python in particular.

548
00:32:19,530 --> 00:32:23,040
We introduced for the first time this
past year something called sentiment

549
00:32:23,040 --> 00:32:28,110
analysis in the area of artificial
intelligence where, at the time--

550
00:32:28,110 --> 00:32:29,610
it was funny at the time--

551
00:32:29,610 --> 00:32:32,100
we wrote code or we
had students write code

552
00:32:32,100 --> 00:32:35,440
to analyze the sentiment of tweets.

553
00:32:35,440 --> 00:32:39,540
So we wanted students to determine if
you read a tweet with your program,

554
00:32:39,540 --> 00:32:42,030
is it a positive, like
a happy tweet, or is it

555
00:32:42,030 --> 00:32:44,310
negative or a mean or angry tweet?

556
00:32:44,310 --> 00:32:46,380
So green or red, for instance.

557
00:32:46,380 --> 00:32:49,950
And we encouraged students
at the time to, for instance,

558
00:32:49,950 --> 00:32:54,360
analyze maybe a certain Donald
Trump's tweets to see just how red

559
00:32:54,360 --> 00:32:57,150
or read they might be and
Hillary Clinton and some

560
00:32:57,150 --> 00:32:58,650
of the other candidates at the time.

561
00:32:58,650 --> 00:33:03,090
And this we gave them a really big file
of positive words and a really big file

562
00:33:03,090 --> 00:33:07,710
of negative words that humans generally
think of as positive versus negative--

563
00:33:07,710 --> 00:33:12,060
beautiful versus ugly, hot versus
cold, or something like that--

564
00:33:12,060 --> 00:33:16,440
they're opposite-type words-- so that
they could then analyze the data.

565
00:33:16,440 --> 00:33:17,910
And then CS50 finance.

566
00:33:17,910 --> 00:33:21,630
We have students write code
and build a web application

567
00:33:21,630 --> 00:33:25,200
using Python and using
SQL, a database language,

568
00:33:25,200 --> 00:33:29,490
via which they implement the notion
of buying and selling stocks.

569
00:33:29,490 --> 00:33:34,530
They write code that gives all of
their users an imaginary $10,000

570
00:33:34,530 --> 00:33:35,910
US, for instance.

571
00:33:35,910 --> 00:33:40,710
And they can then invest that money by
buying or selling stocks and talking

572
00:33:40,710 --> 00:33:46,390
to Yahoo Finance, which provides,
for instance, nearly real time stock

573
00:33:46,390 --> 00:33:46,890
quotes.

574
00:33:46,890 --> 00:33:50,880
And so you have your own website that
simulates what it is to work in finance

575
00:33:50,880 --> 00:33:52,740
or be an investor yourself.

576
00:33:52,740 --> 00:33:54,900
And then lastly, mashup, for instance.

577
00:33:54,900 --> 00:33:57,690
A website that uses JavaScript,
yet another language,

578
00:33:57,690 --> 00:34:02,040
has students implement a map using
Google Maps and their API, so to speak,

579
00:34:02,040 --> 00:34:05,160
their free software so that you
can click and drag and navigate

580
00:34:05,160 --> 00:34:11,020
news articles based on different
cities or countries around the world.

581
00:34:11,020 --> 00:34:14,520
So what is the course
itself structured as?

582
00:34:14,520 --> 00:34:18,090
And where might you see
yourselves in this picture?

583
00:34:18,090 --> 00:34:22,389
So in Cambridge over the past 10-plus
years has enrollment looked like this.

584
00:34:22,389 --> 00:34:26,580
Computer science is there,
say, very popular right now.

585
00:34:26,580 --> 00:34:28,300
When I inherited the
course back then, we

586
00:34:28,300 --> 00:34:31,699
started the year prior with
maybe 100 students give or take.

587
00:34:31,699 --> 00:34:35,420
And we're now up to 700 or
so students every semester.

588
00:34:35,420 --> 00:34:38,230
So there's been this big influx
of students and interest,

589
00:34:38,230 --> 00:34:42,310
but simultaneously has there been
a big investment and a big influx

590
00:34:42,310 --> 00:34:44,199
on our part of support.

591
00:34:44,199 --> 00:34:47,290
For the 700 students we have
at Harvard, for instance,

592
00:34:47,290 --> 00:34:52,120
we have nearly 80 teaching
fellows or course assistants, 80,

593
00:34:52,120 --> 00:34:55,179
who themselves are
almost entirely students.

594
00:34:55,179 --> 00:34:58,360
And this, too, is one of
the unusual aspects of CS50.

595
00:34:58,360 --> 00:35:01,930
It's not just 40-year-olds
like me teaching CS50.

596
00:35:01,930 --> 00:35:03,160
It's undergraduates.

597
00:35:03,160 --> 00:35:06,970
It's students who took the
class just one year ago who,

598
00:35:06,970 --> 00:35:10,240
therefore, are more comfortable than
they used to be with the material.

599
00:35:10,240 --> 00:35:11,440
And they lead the sections.

600
00:35:11,440 --> 00:35:13,150
And they lead the office hours.

601
00:35:13,150 --> 00:35:16,120
And they ultimately teach
their own classmates.

602
00:35:16,120 --> 00:35:17,995
What's been interesting,
too, to see is this.

603
00:35:17,995 --> 00:35:20,060
This is a lot of numbers and colors.

604
00:35:20,060 --> 00:35:23,800
But in blue are students
less comfortable.

605
00:35:23,800 --> 00:35:27,520
In orange are students more comfortable.

606
00:35:27,520 --> 00:35:29,540
In red are somewhere in between.

607
00:35:29,540 --> 00:35:34,240
And so what this means is that
in 2008 about 34% of the class

608
00:35:34,240 --> 00:35:36,670
described themselves
as less comfortable.

609
00:35:36,670 --> 00:35:41,890
Now they're a majority of
the class composing 62%.

610
00:35:41,890 --> 00:35:44,220
Twice as many students essentially.

611
00:35:44,220 --> 00:35:48,400
And so this, too, has required that we
adjust the course's support structure

612
00:35:48,400 --> 00:35:51,610
so that those students with
less experience and less comfort

613
00:35:51,610 --> 00:35:55,490
aren't dropping the class, aren't
struggling more than they need to.

614
00:35:55,490 --> 00:35:58,210
And it's absolutely the case
that for those less comfortable,

615
00:35:58,210 --> 00:36:02,230
less experienced students, the course
will absolutely take a lot of time.

616
00:36:02,230 --> 00:36:05,480
And it might take them more
time, even twice as much time.

617
00:36:05,480 --> 00:36:09,220
But the key ingredient and
design principle underlying CS50

618
00:36:09,220 --> 00:36:13,000
is that all students,
irrespective of their background,

619
00:36:13,000 --> 00:36:16,270
should be able to succeed
given the right resources

620
00:36:16,270 --> 00:36:19,270
and given the right amount of time.

621
00:36:19,270 --> 00:36:21,370
And here's just a glimpse
then, for instance,

622
00:36:21,370 --> 00:36:25,630
of the teaching team we have at
Harvard teaching CS50 last fall.

623
00:36:25,630 --> 00:36:28,360
And almost all of the
faces pictured here

624
00:36:28,360 --> 00:36:33,437
were themselves students who took the
class one or two or three years prior.

625
00:36:33,437 --> 00:36:35,020
What does the course itself look like?

626
00:36:35,020 --> 00:36:38,950
It has lectures once a week in a
place like Sanders Theater or on video

627
00:36:38,950 --> 00:36:43,790
for students to watch, sections,
which are smaller classes with 10, 20,

628
00:36:43,790 --> 00:36:47,830
30 students and one teaching fellow
reviewing material, answering

629
00:36:47,830 --> 00:36:50,350
questions, and doing what we
couldn't really do in a space

630
00:36:50,350 --> 00:36:51,940
as large as this together.

631
00:36:51,940 --> 00:36:52,990
And then office hours.

632
00:36:52,990 --> 00:36:54,640
And this, too, is a key detail.

633
00:36:54,640 --> 00:36:57,377
We have a space on campus, much
like the space you have here

634
00:36:57,377 --> 00:36:59,710
with all the photographs on
the wall, where students can

635
00:36:59,710 --> 00:37:02,620
go for help really throughout the week.

636
00:37:02,620 --> 00:37:06,100
At almost any hour at Harvard
can students drop in on a space,

637
00:37:06,100 --> 00:37:09,220
meet some of their classmates and
meet some of the teaching fellows

638
00:37:09,220 --> 00:37:14,530
and ultimately get their questions
answered on some homework assignments.

639
00:37:14,530 --> 00:37:18,760
And if you're curious and if you're
in CS50 now and you've been struggling

640
00:37:18,760 --> 00:37:21,100
or maybe you were in CS50
and struggled and thought,

641
00:37:21,100 --> 00:37:23,950
wow, this isn't for me, because
look at how much time it's taking,

642
00:37:23,950 --> 00:37:26,320
I mean, here at Harvard
these lines represent

643
00:37:26,320 --> 00:37:28,210
the average number of
hours students tend

644
00:37:28,210 --> 00:37:30,610
to take on each of the problem sets.

645
00:37:30,610 --> 00:37:33,850
The horizontal line here means it
was about six hours for problem

646
00:37:33,850 --> 00:37:34,884
set zero for Scratch.

647
00:37:34,884 --> 00:37:38,050
And that's about right if you get into
it and you might have some struggles.

648
00:37:38,050 --> 00:37:40,270
But then certainly later
in the semester the average

649
00:37:40,270 --> 00:37:43,300
is closer to 12 or 15 hours.

650
00:37:43,300 --> 00:37:44,950
And that's important to note.

651
00:37:44,950 --> 00:37:48,130
Because it's very normal and
it's very usual for students

652
00:37:48,130 --> 00:37:49,570
to take a lot of time.

653
00:37:49,570 --> 00:37:53,220
And indeed, even myself, I don't
consider myself a fast programmer.

654
00:37:53,220 --> 00:37:55,510
I don't know if I consider
myself a great programmer.

655
00:37:55,510 --> 00:37:57,880
I just know that if
I do put in the time,

656
00:37:57,880 --> 00:38:01,310
and I sort of take things step
by step and methodically, I

657
00:38:01,310 --> 00:38:02,980
will always find the solution.

658
00:38:02,980 --> 00:38:06,610
And that, honestly, has been very
empowering if not challenging

659
00:38:06,610 --> 00:38:10,900
in computer science and in programming
specifically at least at this level

660
00:38:10,900 --> 00:38:14,800
when you're just learning material and
you're learning what others before you

661
00:38:14,800 --> 00:38:16,030
have discovered already.

662
00:38:16,030 --> 00:38:18,280
And that's, of course,
the even harder part.

663
00:38:18,280 --> 00:38:19,540
There's always an answer.

664
00:38:19,540 --> 00:38:22,270
There's always a way to
get your code correct.

665
00:38:22,270 --> 00:38:23,530
You just need to find it.

666
00:38:23,530 --> 00:38:25,030
You just need to see it.

667
00:38:25,030 --> 00:38:27,976
And it's very gratifying
when you finally do.

668
00:38:27,976 --> 00:38:30,100
But of course, it's not
just all this kind of work.

669
00:38:30,100 --> 00:38:32,500
As some of you have experienced,
CS50 is characterized

670
00:38:32,500 --> 00:38:36,310
by these cultural aspects, these
experiences that, frankly, most classes

671
00:38:36,310 --> 00:38:37,560
don't really have.

672
00:38:37,560 --> 00:38:39,820
CS50 Puzzle Day is an
opportunity at the start

673
00:38:39,820 --> 00:38:43,510
of the year for students to get
together and not work on code,

674
00:38:43,510 --> 00:38:48,220
not even use computers necessarily, but
to solve problems, puzzles, riddles,

675
00:38:48,220 --> 00:38:51,460
and word problems really to send
the message that computer science is

676
00:38:51,460 --> 00:38:52,990
about problem-solving.

677
00:38:52,990 --> 00:38:54,600
It is not programming.

678
00:38:54,600 --> 00:38:57,100
Even though one of the things
you'll spend most of your time

679
00:38:57,100 --> 00:38:59,860
on in an introductory
class is programming,

680
00:38:59,860 --> 00:39:04,940
it's just a tool that you use to solve
problems and think about problems.

681
00:39:04,940 --> 00:39:07,660
Here is CS50 Puzzle Day in Cambridge.

682
00:39:07,660 --> 00:39:11,200
Here is CS50 Puzzle Day in Nicaragua.

683
00:39:11,200 --> 00:39:15,710
Here is a recent lunch
in CS50 back home.

684
00:39:15,710 --> 00:39:16,990
This is purely social.

685
00:39:16,990 --> 00:39:21,490
Like once a week do we get together
with 50 or so students just to chat

686
00:39:21,490 --> 00:39:25,000
and just to talk about maybe the
course, but probably more likely

687
00:39:25,000 --> 00:39:28,690
what else they do at school or
what you can do after class,

688
00:39:28,690 --> 00:39:30,160
what you can do in industry.

689
00:39:30,160 --> 00:39:33,130
And we invite alumni and
friends from local companies

690
00:39:33,130 --> 00:39:35,710
to join us for lunch just
to chat with students

691
00:39:35,710 --> 00:39:38,500
about why they're taking a class
like this in the first place

692
00:39:38,500 --> 00:39:41,020
and how it applies to the real world.

693
00:39:41,020 --> 00:39:43,490
The CS50 Hackathon we
started some years ago.

694
00:39:43,490 --> 00:39:46,090
We borrowed the idea from
our friends at Facebook.

695
00:39:46,090 --> 00:39:50,260
And the hackathon, in our
case, is a 12-hour opportunity

696
00:39:50,260 --> 00:39:53,730
from 7:00 PM at night to
7:00 AM In the morning

697
00:39:53,730 --> 00:39:55,660
to just work on your final projects.

698
00:39:55,660 --> 00:39:58,630
But more than that, have
this shared experience

699
00:39:58,630 --> 00:40:00,760
with friends and with
classmates, all of whom

700
00:40:00,760 --> 00:40:04,330
might be struggling with similar
things and going through it together.

701
00:40:04,330 --> 00:40:08,170
To be fair, staying up all night
is a challenge unto itself.

702
00:40:08,170 --> 00:40:13,786
But in our case, we serve pizza at 9:00
PM, usually Chinese food at 1:00 AM.

703
00:40:13,786 --> 00:40:15,660
And then as you may have
seen from the video,

704
00:40:15,660 --> 00:40:17,868
there's this place in the
US called the International

705
00:40:17,868 --> 00:40:22,240
House of Pancakes or IHOP, which is
not really international in any sense.

706
00:40:22,240 --> 00:40:23,020
But we go there.

707
00:40:23,020 --> 00:40:26,800
We drive there at 5:00 AM with anyone
who's still awake at that hour.

708
00:40:26,800 --> 00:40:28,780
But of course, not everyone makes it.

709
00:40:28,780 --> 00:40:31,640
This was 4:00 AM one year, for instance.

710
00:40:31,640 --> 00:40:33,880
But by far, one of the
most exciting things

711
00:40:33,880 --> 00:40:36,420
and one of the exciting
goals of the class

712
00:40:36,420 --> 00:40:38,890
is something like this, our CS50 Fair.

713
00:40:38,890 --> 00:40:40,330
And it didn't start this big.

714
00:40:40,330 --> 00:40:42,370
It was certainly much
smaller in its first year.

715
00:40:42,370 --> 00:40:45,730
But it's grown to be an
event every year with 2000

716
00:40:45,730 --> 00:40:49,390
or more people coming to
see students' final projects

717
00:40:49,390 --> 00:40:52,030
and to see what you can
do with computer science.

718
00:40:52,030 --> 00:40:55,510
And indeed, most of the students
who take CS50 at Harvard,

719
00:40:55,510 --> 00:40:57,220
they're not computer science students.

720
00:40:57,220 --> 00:40:59,590
They're not going to
major in computer science.

721
00:40:59,590 --> 00:41:04,510
90% of them are studying some other
field, economics, social sciences,

722
00:41:04,510 --> 00:41:07,740
natural sciences, medicine, the arts.

723
00:41:07,740 --> 00:41:11,500
And for instance, I grabbed a few
photos and names from this past year.

724
00:41:11,500 --> 00:41:16,535
Two students named [? Lira ?] and Sarah
implemented an app called Audio Chrome.

725
00:41:16,535 --> 00:41:17,410
And this was an app--

726
00:41:17,410 --> 00:41:19,450
I mentioned this to some
of the TFs yesterday--

727
00:41:19,450 --> 00:41:23,440
where if you're color-blind, you can't
see colors properly with your eyes,

728
00:41:23,440 --> 00:41:26,790
but you do have a phone, you can
point your phone at something

729
00:41:26,790 --> 00:41:29,680
and decide just what
color these flowers are.

730
00:41:29,680 --> 00:41:32,260
Or more compellingly when
getting dressed in the morning,

731
00:41:32,260 --> 00:41:35,140
do these pants match
this shirt or this tie?

732
00:41:35,140 --> 00:41:37,180
Because the phone can
answer questions that you,

733
00:41:37,180 --> 00:41:38,960
yourself, might not be able to.

734
00:41:38,960 --> 00:41:42,940
And they implemented software
for iPhone that did exactly that.

735
00:41:42,940 --> 00:41:45,190
Nick, for instance, is a musician.

736
00:41:45,190 --> 00:41:48,730
And he can read sheet music
on paper or on the screen.

737
00:41:48,730 --> 00:41:52,480
And he wrote software that
converted musical notes on scales

738
00:41:52,480 --> 00:41:56,380
like this to actual
computer readable data

739
00:41:56,380 --> 00:41:58,760
so that it could then be
synthesized by the computer,

740
00:41:58,760 --> 00:42:01,270
even though it had started
in this form, using something

741
00:42:01,270 --> 00:42:04,930
called optical character recognition,
letting the computer and machine

742
00:42:04,930 --> 00:42:08,840
vision, so to speak, figure
out what those notes represent.

743
00:42:08,840 --> 00:42:13,030
Lucas here was using Amazon
Alexa, I believe, here.

744
00:42:13,030 --> 00:42:15,280
He's talking into it on
the right-hand side there.

745
00:42:15,280 --> 00:42:16,840
And it was connected to his computer.

746
00:42:16,840 --> 00:42:20,500
Because Alexa, like a Google Home
and a lot of these new devices

747
00:42:20,500 --> 00:42:25,360
that are voice-activated, have APIs,
application programming interfaces,

748
00:42:25,360 --> 00:42:27,580
via which you can teach
them to do new things

749
00:42:27,580 --> 00:42:30,430
and do projects that are of
interest to you, not just what

750
00:42:30,430 --> 00:42:35,370
Amazon or Google or other companies
decide you should have in your home.

751
00:42:35,370 --> 00:42:39,797
Jeanette, Ken, and Mary here implemented
something called Drop the Ramen.

752
00:42:39,797 --> 00:42:42,130
At least in the US it's very
common for college students

753
00:42:42,130 --> 00:42:46,360
to eat a lot of ramen or dried
noodles late at night, for instance.

754
00:42:46,360 --> 00:42:49,060
And they wrote an app that makes
it a lot easier for students

755
00:42:49,060 --> 00:42:53,350
to figure out healthier meals to make
using the limited ingredients they

756
00:42:53,350 --> 00:42:54,760
might actually have.

757
00:42:54,760 --> 00:42:56,560
And then this one too.

758
00:42:56,560 --> 00:43:00,670
I didn't even know before
meeting Luke at Yale a year ago

759
00:43:00,670 --> 00:43:01,900
that this data was collected.

760
00:43:01,900 --> 00:43:05,290
But it turns out in the NBA,
the basketball association,

761
00:43:05,290 --> 00:43:08,170
and in a lot of sports, they
collect a huge amount of data now.

762
00:43:08,170 --> 00:43:10,810
For instance, if you shoot a
shot in a basketball court,

763
00:43:10,810 --> 00:43:13,510
they very often use
computers to record where

764
00:43:13,510 --> 00:43:16,300
that shot was taken physically
on the floor, who took it,

765
00:43:16,300 --> 00:43:18,490
did it actually go into the net or not.

766
00:43:18,490 --> 00:43:22,480
And so Luke used this data and
actually made a visualization here,

767
00:43:22,480 --> 00:43:26,980
for instance, of LeBron James actually
depicting where in green he made shots,

768
00:43:26,980 --> 00:43:31,510
where in red he missed shots, thereby
merging the ideas of visualization

769
00:43:31,510 --> 00:43:34,210
and programming to actually do
something that could help you,

770
00:43:34,210 --> 00:43:37,030
the athlete, perhaps make better
sense of where you're good.

771
00:43:37,030 --> 00:43:38,920
Apparently, layups are pretty easy.

772
00:43:38,920 --> 00:43:41,420
So there's a lot of green over here.

773
00:43:41,420 --> 00:43:44,110
And it's not necessarily clear
if there is a pattern elsewhere.

774
00:43:44,110 --> 00:43:46,450
But perhaps there is
and you can get better

775
00:43:46,450 --> 00:43:49,090
at what it is you do as a result.

776
00:43:49,090 --> 00:43:52,590
And you see ultimately at the
CS50 Fair faces like these

777
00:43:52,590 --> 00:43:54,340
and faces of your own
classmates hopefully

778
00:43:54,340 --> 00:43:57,730
delighting in the kind of projects
that have been implemented.

779
00:43:57,730 --> 00:43:59,652
And that, too, is
ultimately one of the goals.

780
00:43:59,652 --> 00:44:01,360
To actually be proud
of something you do.

781
00:44:01,360 --> 00:44:03,580
And not just do homework
week after week,

782
00:44:03,580 --> 00:44:07,270
but to build something
that's ultimately your own.

783
00:44:07,270 --> 00:44:11,800
Now in CS50x, from which CS50x
Nicaragua is derivative, of course,

784
00:44:11,800 --> 00:44:13,840
it is exactly the same curriculum.

785
00:44:13,840 --> 00:44:15,550
It is exactly the same tools.

786
00:44:15,550 --> 00:44:18,070
And ideally, it's exactly
the same experience.

787
00:44:18,070 --> 00:44:21,100
We don't have the luxury of
being in the same physical place,

788
00:44:21,100 --> 00:44:23,380
but do we have opportunities
for our students online

789
00:44:23,380 --> 00:44:26,800
to have Puzzle Day
experiences and fairs online

790
00:44:26,800 --> 00:44:30,410
and to meet locally with students
much like is happening here.

791
00:44:30,410 --> 00:44:32,890
We typically stretch that
version of the class--

792
00:44:32,890 --> 00:44:34,150
freely available through edX--

793
00:44:34,150 --> 00:44:36,670
over 52 weeks, a full year.

794
00:44:36,670 --> 00:44:39,670
And the workload is
ultimately almost the same.

795
00:44:39,670 --> 00:44:42,700
The nine homework assignments
and the final project, but not,

796
00:44:42,700 --> 00:44:45,820
for instance, the exams, simply
because most students taking

797
00:44:45,820 --> 00:44:48,010
the course through edX
are really doing it just

798
00:44:48,010 --> 00:44:50,890
for their own interest and
edification and there's not

799
00:44:50,890 --> 00:44:52,360
that same need for rigor.

800
00:44:52,360 --> 00:44:55,490
But for those students do we
have huge communities online.

801
00:44:55,490 --> 00:44:57,490
You might recognize some
of these websites here,

802
00:44:57,490 --> 00:45:01,930
certainly Facebook and Twitter,
but also Reddit and Stack Exchange

803
00:45:01,930 --> 00:45:04,540
and, oh, there's still
Slack nowadays, too,

804
00:45:04,540 --> 00:45:07,720
where right now if I went
into CS50's Facebook group,

805
00:45:07,720 --> 00:45:11,230
and you guys have your own here for
CS50x Nicaragua, within minutes,

806
00:45:11,230 --> 00:45:13,630
typically, if I post a
question in that community

807
00:45:13,630 --> 00:45:17,320
with some 100,000 Facebook
users, you get an answer.

808
00:45:17,320 --> 00:45:19,814
And you might actually be
able to connect with them

809
00:45:19,814 --> 00:45:21,230
and see students around the world.

810
00:45:21,230 --> 00:45:23,500
And this has been one of
the most impactful things

811
00:45:23,500 --> 00:45:27,790
by far how students across the world,
who wouldn't otherwise necessarily have

812
00:45:27,790 --> 00:45:31,540
need or opportunity to meet each
other or talk about something,

813
00:45:31,540 --> 00:45:34,090
coming together to
share in some experience

814
00:45:34,090 --> 00:45:36,610
and ultimately learn some topic.

815
00:45:36,610 --> 00:45:41,320
At Yale, meanwhile, this has been one
of our most tight-knit relationships.

816
00:45:41,320 --> 00:45:44,050
Historically, Harvard and
Yale are kind of competitors.

817
00:45:44,050 --> 00:45:48,010
And we are single-handedly trying
to solve 300 years of strife.

818
00:45:48,010 --> 00:45:51,470
But in this case do we have students
taking the same course at both Harvard

819
00:45:51,470 --> 00:45:51,970
and Yale.

820
00:45:51,970 --> 00:45:55,390
And most importantly do we have
undergraduate teaching fellows

821
00:45:55,390 --> 00:45:57,760
teaching the class on both campuses.

822
00:45:57,760 --> 00:46:00,850
And this was the proverbial chicken
and the egg problem at first.

823
00:46:00,850 --> 00:46:05,620
If CS50 is mostly taught not just by
me, but by our undergraduate teaching

824
00:46:05,620 --> 00:46:08,110
fellows or course
assistants as we call them,

825
00:46:08,110 --> 00:46:10,630
well, it's kind of hard to do
that at Yale if no one at Yale

826
00:46:10,630 --> 00:46:12,430
has ever taken CS50.

827
00:46:12,430 --> 00:46:14,950
And so we spent quite a bit
of time the previous year

828
00:46:14,950 --> 00:46:19,090
training students, having them do the
course's problem sets on their own,

829
00:46:19,090 --> 00:46:23,110
and ultimately bootstrapping, so
to speak, a support structure,

830
00:46:23,110 --> 00:46:26,530
so that now they are on their
way to functioning exactly

831
00:46:26,530 --> 00:46:28,450
as we have in Cambridge.

832
00:46:28,450 --> 00:46:32,110
And indeed, this was one of the event
where we first recruited students

833
00:46:32,110 --> 00:46:32,640
to teach.

834
00:46:32,640 --> 00:46:34,900
And indeed, one of the
most remarkable things

835
00:46:34,900 --> 00:46:39,070
here is, too, the idea of undergraduate
students-- students in university--

836
00:46:39,070 --> 00:46:42,640
teaching other students in university
is sometimes controversial.

837
00:46:42,640 --> 00:46:45,580
Even at Harvard, most
departments do not allow this.

838
00:46:45,580 --> 00:46:50,500
And the reality was that Yale as the
result of CS50 being taught there, Yale

839
00:46:50,500 --> 00:46:54,490
University, after 200 years,
now allows undergraduates

840
00:46:54,490 --> 00:46:57,640
to teach other undergraduates
in roles like this.

841
00:46:57,640 --> 00:47:00,760
And this is now something they're
rolling out to other computer science

842
00:47:00,760 --> 00:47:02,450
courses at Yale as well.

843
00:47:02,450 --> 00:47:06,910
And so this was our first cohort of
Yale students just over a year ago.

844
00:47:06,910 --> 00:47:08,950
And this was their CS50 Fair.

845
00:47:08,950 --> 00:47:12,680
They, too, have a very
Hogwarts-like space as well.

846
00:47:12,680 --> 00:47:15,790
Now, if curious, CS50
for MBAs is different.

847
00:47:15,790 --> 00:47:18,880
It focuses not so much on
that same broad community

848
00:47:18,880 --> 00:47:22,930
and focuses not so much on that
hands-on building of software,

849
00:47:22,930 --> 00:47:27,010
but it focuses on ideas, cloud
computing, programming languages

850
00:47:27,010 --> 00:47:30,040
in general database design,
computational thinking,

851
00:47:30,040 --> 00:47:34,300
a lot of the ingredients that a computer
scientist and engineer ultimately

852
00:47:34,300 --> 00:47:36,430
learns in courses
about computer science,

853
00:47:36,430 --> 00:47:38,980
but that's because he or
she in a course like CS50

854
00:47:38,980 --> 00:47:41,890
itself is going to use
those skills themselves.

855
00:47:41,890 --> 00:47:45,580
But it's incredibly and increasingly
important in business or in politics

856
00:47:45,580 --> 00:47:50,230
or in any number of fields just to
understand what is the cloud, right?

857
00:47:50,230 --> 00:47:53,020
Odds are everyone in this
room has heard of the cloud.

858
00:47:53,020 --> 00:47:55,255
But if I may, what is the cloud?

859
00:47:55,255 --> 00:47:58,190


860
00:47:58,190 --> 00:47:58,940
What is the cloud?

861
00:47:58,940 --> 00:47:59,470
Yes.

862
00:47:59,470 --> 00:48:02,831
AUDIENCE: It's a virtual space in many
servers spread across the world, where

863
00:48:02,831 --> 00:48:03,872
people store information.

864
00:48:03,872 --> 00:48:05,276
You can access it from anywhere.

865
00:48:05,276 --> 00:48:06,290
DAVID J. MALAN: Yeah, absolutely.

866
00:48:06,290 --> 00:48:06,994
Virtual space.

867
00:48:06,994 --> 00:48:07,910
Anywhere in the world.

868
00:48:07,910 --> 00:48:09,950
Servers that you can use
anywhere in the world.

869
00:48:09,950 --> 00:48:13,220
But at the end of the day,
frankly, this and so many terms

870
00:48:13,220 --> 00:48:18,930
really are just marketing phrases to
describe more interesting technologies.

871
00:48:18,930 --> 00:48:23,120
In this case, the cloud is really just
about using someone else's servers.

872
00:48:23,120 --> 00:48:25,310
And this has been possible for decades.

873
00:48:25,310 --> 00:48:27,254
But once you put a
nice little icon on it

874
00:48:27,254 --> 00:48:29,420
and you call it iCloud and
the like do you have what

875
00:48:29,420 --> 00:48:33,740
seems to be a whole new technology that
you're not necessarily keeping up with.

876
00:48:33,740 --> 00:48:37,850
But the reality is, the underlying
technologies are largely invariant.

877
00:48:37,850 --> 00:48:40,210
And so with our MBA and
our business students

878
00:48:40,210 --> 00:48:43,550
do we help them try to sift
through what is meaningful,

879
00:48:43,550 --> 00:48:45,890
what are just buzzwords or
expressions so that they

880
00:48:45,890 --> 00:48:48,680
can make better decisions,
ultimately, and actually

881
00:48:48,680 --> 00:48:52,520
know what the cloud, so to speak, offers
in terms of actually solving business

882
00:48:52,520 --> 00:48:55,440
problems or costs that they might have.

883
00:48:55,440 --> 00:48:58,310
And then lastly, the last
flavor of CS50 at scale

884
00:48:58,310 --> 00:49:01,590
now is this, CS50 AP
or advanced placement,

885
00:49:01,590 --> 00:49:04,730
which is just an adaptation of
the course for high schools using

886
00:49:04,730 --> 00:49:07,970
the same curriculum,
the same technologies,

887
00:49:07,970 --> 00:49:11,900
but spread over, typically,
36 weeks, give or take,

888
00:49:11,900 --> 00:49:14,840
with what are required
by the AP College Board.

889
00:49:14,840 --> 00:49:16,760
The College Board is a
group that essentially

890
00:49:16,760 --> 00:49:18,770
decrees how you standardize tests.

891
00:49:18,770 --> 00:49:22,550
And so in CS50 AP there's
not just the problem sets.

892
00:49:22,550 --> 00:49:27,410
There's performance tasks and an
exam that's required for AP credit.

893
00:49:27,410 --> 00:49:29,600
But this is really just
an implementation detail.

894
00:49:29,600 --> 00:49:34,130
What's important with CS50 AP
that in 2015 it represented

895
00:49:34,130 --> 00:49:36,110
a significant change on our part.

896
00:49:36,110 --> 00:49:39,500
For many years had we focused
almost entirely on students--

897
00:49:39,500 --> 00:49:42,290
providing students with
freely available resources

898
00:49:42,290 --> 00:49:46,350
and homework assignments and tools
and sample solutions and the like--

899
00:49:46,350 --> 00:49:50,540
but we didn't really focus at all on
teachers and sort of uplifting teachers

900
00:49:50,540 --> 00:49:54,060
to be more comfortable themselves
so that we could achieve ultimately

901
00:49:54,060 --> 00:49:57,200
more of a network effect,
more of an exponentiation.

902
00:49:57,200 --> 00:49:59,840
We've never thought it's
interesting, frankly, in CS50

903
00:49:59,840 --> 00:50:05,000
that we had, like, 1 million
students who've registered for CS50x.

904
00:50:05,000 --> 00:50:08,420
I don't think we can do an especially
good job teaching, on our own,

905
00:50:08,420 --> 00:50:12,330
100,000 or 200,000 people
at that kind of scale.

906
00:50:12,330 --> 00:50:16,040
Far more important is
to have people locally

907
00:50:16,040 --> 00:50:18,500
supporting students
and answering questions

908
00:50:18,500 --> 00:50:20,370
and creating those local communities.

909
00:50:20,370 --> 00:50:23,150
And this is exactly by
way of these resources

910
00:50:23,150 --> 00:50:26,720
what we now provide to our teachers,
both at the university level,

911
00:50:26,720 --> 00:50:29,460
but also and initially
at the high school level

912
00:50:29,460 --> 00:50:31,520
so that they have absolutely
as much as they need

913
00:50:31,520 --> 00:50:33,740
and so that they don't,
as in the US, need

914
00:50:33,740 --> 00:50:37,310
to just adopt curriculum that
come from textbook companies,

915
00:50:37,310 --> 00:50:40,950
for instance, who have traditionally
decreed what a class would be like.

916
00:50:40,950 --> 00:50:44,000
But teachers can now use
this as a menu of options.

917
00:50:44,000 --> 00:50:47,150
We also provide our teachers
with CS50 Puzzle Day in a box

918
00:50:47,150 --> 00:50:49,580
and the hackathon in the
box in the fair in the box.

919
00:50:49,580 --> 00:50:52,700
So boxes of just swag and
fun things and the puzzles

920
00:50:52,700 --> 00:50:57,830
themselves so that teachers can run
these events at their own places.

921
00:50:57,830 --> 00:51:01,280
So ultimately, and we were chatting
a few of us about this just a little

922
00:51:01,280 --> 00:51:04,730
bit ago, there's really three
characteristics that characterize

923
00:51:04,730 --> 00:51:07,910
CS50 at Harvard and also CS50 at scale.

924
00:51:07,910 --> 00:51:10,130
It's that first and
foremost accessibility.

925
00:51:10,130 --> 00:51:13,880
Trying to create an educational
experience at which any student can

926
00:51:13,880 --> 00:51:18,290
succeed irrespective of his or
her prior experience in CS or not,

927
00:51:18,290 --> 00:51:22,160
changing that slope, so to speak,
that on ramp, but maintaining,

928
00:51:22,160 --> 00:51:26,510
ultimately, the rigor that the course
in the field itself has long had.

929
00:51:26,510 --> 00:51:30,620
It's very easy, I daresay, to
make a popular very large class

930
00:51:30,620 --> 00:51:34,740
by just lowering your expectations and
making it easier and making it fun,

931
00:51:34,740 --> 00:51:36,560
but really watering it down.

932
00:51:36,560 --> 00:51:40,147
But what's so, I think, impactful
about a more rigorous introduction

933
00:51:40,147 --> 00:51:42,230
is that of all the classes
that you might have had

934
00:51:42,230 --> 00:51:44,521
and, frankly, of all the
classes I might have had, it's

935
00:51:44,521 --> 00:51:47,690
those where I put in the most
time, and struggle the most,

936
00:51:47,690 --> 00:51:51,110
and yet somehow still like the
most that I feel in retrospect,

937
00:51:51,110 --> 00:51:53,330
wow, like, that was worthwhile.

938
00:51:53,330 --> 00:51:56,390
I might not want to take four
of those classes a semester

939
00:51:56,390 --> 00:52:01,070
or more classes a semester, but among
those defining educational experiences

940
00:52:01,070 --> 00:52:03,860
you have, whether it's in CS
or any other field, the ones

941
00:52:03,860 --> 00:52:07,370
that you're really proud of
what you achieve at the end.

942
00:52:07,370 --> 00:52:10,700
And indeed, I thought I would end with
just this visual, one of the aspects

943
00:52:10,700 --> 00:52:12,650
of which we are ourselves so proud.

944
00:52:12,650 --> 00:52:14,990
You'll recognize some
familiar faces here.

945
00:52:14,990 --> 00:52:18,530
It's been such an honor to be here
today and yesterday and tomorrow.

946
00:52:18,530 --> 00:52:22,640
And so thank you all, to Carlos and
Sylvio and all of our hosts here today.

947
00:52:22,640 --> 00:52:24,110
I'm happy to take any questions.

948
00:52:24,110 --> 00:52:27,536
But this then was CS50.

949
00:52:27,536 --> 00:52:31,440
[APPLAUSE]

950
00:52:31,440 --> 00:52:38,272


951
00:52:38,272 --> 00:52:39,980
AUDIENCE: I was
wondering how you managed

952
00:52:39,980 --> 00:52:42,664
to overcome that initial
hesitation from a school

953
00:52:42,664 --> 00:52:44,640
to allow undergraduates to teach.

954
00:52:44,640 --> 00:52:48,000
DAVID J. MALAN: How did we overcome
the initial hesitation of the school

955
00:52:48,000 --> 00:52:49,560
to allow undergraduates?

956
00:52:49,560 --> 00:52:53,170
Thankfully at Harvard someone
else did this 40 years ago.

957
00:52:53,170 --> 00:52:56,460
So Harvard has, thankfully, had
this tradition for a long time.

958
00:52:56,460 --> 00:52:59,460
At Yale it was, I
think, more challenging.

959
00:52:59,460 --> 00:53:03,660
Their entire faculty at the college
had to vote on this opportunity.

960
00:53:03,660 --> 00:53:07,740
And honestly, strategically, I think it
was well-positioned as an experiment.

961
00:53:07,740 --> 00:53:10,560
And indeed, we framed this
whole collaboration with Yale

962
00:53:10,560 --> 00:53:11,430
as an experiment.

963
00:53:11,430 --> 00:53:12,180
Three years.

964
00:53:12,180 --> 00:53:15,810
Being scientists, we like
to collect data and analyze.

965
00:53:15,810 --> 00:53:18,360
And I think creating
those kinds of safe spaces

966
00:53:18,360 --> 00:53:22,260
where you're not proposing to change
100 years of history at Harvard or Yale

967
00:53:22,260 --> 00:53:23,800
or here or elsewhere.

968
00:53:23,800 --> 00:53:25,890
You're really just trying
to try something new.

969
00:53:25,890 --> 00:53:30,030
You're scoping it, in a way, that
if it fails, it's not a huge failure

970
00:53:30,030 --> 00:53:31,950
and it's not all that
impactful, but you also

971
00:53:31,950 --> 00:53:33,900
don't create this sort
of knee-jerk reaction

972
00:53:33,900 --> 00:53:37,960
that some folks have by saying no
to something just because it's new.

973
00:53:37,960 --> 00:53:41,130
So I think framing it as an
experiment and defining for yourself,

974
00:53:41,130 --> 00:53:43,840
like, what will it mean for
this to be successful or not,

975
00:53:43,840 --> 00:53:46,980
I think is something that
academics can hopefully

976
00:53:46,980 --> 00:53:48,770
get comfortable with much more readily.

977
00:53:48,770 --> 00:53:49,810
AUDIENCE: Thank you.

978
00:53:49,810 --> 00:53:51,310
DAVID J. MALAN: Any other questions?

979
00:53:51,310 --> 00:53:51,810
Please.

980
00:53:51,810 --> 00:53:53,960
AUDIENCE: When will you
take it to grade school?

981
00:53:53,960 --> 00:53:55,540
DAVID J. MALAN: Grade school!

982
00:53:55,540 --> 00:53:57,760
We're not sure how
quickly that would happen.

983
00:53:57,760 --> 00:53:59,230
We do already have--

984
00:53:59,230 --> 00:54:03,340
beyond high school we've
estimated that age 13 or 14 or 15

985
00:54:03,340 --> 00:54:04,900
is reasonable to begin.

986
00:54:04,900 --> 00:54:06,070
We have counterexamples.

987
00:54:06,070 --> 00:54:06,569
To this.

988
00:54:06,569 --> 00:54:08,830
Just yesterday on CS50's
the Facebook group

989
00:54:08,830 --> 00:54:13,060
I posted a video of a young
lady who's 11 years old,

990
00:54:13,060 --> 00:54:16,750
Presley, who has actually been
taking CS50 for some time.

991
00:54:16,750 --> 00:54:20,950
But we're now only beginning to think
about how we might create not CS50,

992
00:54:20,950 --> 00:54:25,600
per se, but entry points to
computer science for younger kids.

993
00:54:25,600 --> 00:54:31,592
AUDIENCE: [INAUDIBLE]

994
00:54:31,592 --> 00:54:33,800
DAVID J. MALAN: It depends
on the community thus far.

995
00:54:33,800 --> 00:54:35,900
The team here has done
an extraordinary job

996
00:54:35,900 --> 00:54:38,760
at translating the most important
materials, for instance,

997
00:54:38,760 --> 00:54:41,789
the problem sets or subtitles
on the English lectures.

998
00:54:41,789 --> 00:54:43,580
This is something we
in Cambridge now we're

999
00:54:43,580 --> 00:54:47,510
going to start focusing more on now that
we've identified some very-- we have

1000
00:54:47,510 --> 00:54:50,600
critical mass among certain
cultures or certain languages

1001
00:54:50,600 --> 00:54:53,480
so that we can start
helping with this as well.

1002
00:54:53,480 --> 00:54:55,730
With that said, in the world
of programming at least,

1003
00:54:55,730 --> 00:54:58,640
which CS50 has a lot of,
the reality is the languages

1004
00:54:58,640 --> 00:55:01,930
and the communities online
are so largely English driven.

1005
00:55:01,930 --> 00:55:03,750
It's not a bad thing necessarily.

1006
00:55:03,750 --> 00:55:06,830
But certainly for students
for whom the world is so new,

1007
00:55:06,830 --> 00:55:09,530
I think it's best that I'm not
speaking entirely in English.

1008
00:55:09,530 --> 00:55:11,360
But they can be more
comfortable with that

1009
00:55:11,360 --> 00:55:16,541
and then focus on the more
technical stuff in English.

1010
00:55:16,541 --> 00:55:17,040
Yes.

1011
00:55:17,040 --> 00:55:17,540
In back.

1012
00:55:17,540 --> 00:55:23,276
AUDIENCE: Can someone be part of
the course without [INAUDIBLE] like,

1013
00:55:23,276 --> 00:55:26,727
my peers [INAUDIBLE]
people, just like, yourself

1014
00:55:26,727 --> 00:55:28,905
and your school wherever you are?

1015
00:55:28,905 --> 00:55:30,030
DAVID J. MALAN: Absolutely.

1016
00:55:30,030 --> 00:55:31,450
Can you be part of the class?

1017
00:55:31,450 --> 00:55:33,970
Can you take it independent
of a formal structure

1018
00:55:33,970 --> 00:55:35,470
here or some other university?

1019
00:55:35,470 --> 00:55:36,110
Absolutely.

1020
00:55:36,110 --> 00:55:38,620
The easiest way is just
to sign up for free

1021
00:55:38,620 --> 00:55:43,205
on cs50.edx.org to identify the
friends or classmates here or elsewhere

1022
00:55:43,205 --> 00:55:45,580
in the world that you want to
do it with and just come up

1023
00:55:45,580 --> 00:55:46,820
with your own schedule.

1024
00:55:46,820 --> 00:55:50,080
We propose that students take a few
weeks per problem set through edX.

1025
00:55:50,080 --> 00:55:52,550
But you can certainly
do whatever you want.

1026
00:55:52,550 --> 00:55:53,290
So absolutely.

1027
00:55:53,290 --> 00:55:56,530
And if you go to cs50.org,
you'll see more information

1028
00:55:56,530 --> 00:55:59,020
about how to stand up
your own local community.

1029
00:55:59,020 --> 00:56:01,810
And indeed, for instance,
at University College London

1030
00:56:01,810 --> 00:56:05,470
in the UK we have a student
group, the group of students

1031
00:56:05,470 --> 00:56:08,320
who are interested in technology,
they're just doing it on their own

1032
00:56:08,320 --> 00:56:09,970
for fun and for their classmates.

1033
00:56:09,970 --> 00:56:11,270
It's not a class, per se.

1034
00:56:11,270 --> 00:56:12,230
It's not for credit.

1035
00:56:12,230 --> 00:56:15,466
But they're doing that
at an even larger scale.

1036
00:56:15,466 --> 00:56:17,360
Please.

1037
00:56:17,360 --> 00:56:23,040
AUDIENCE: Have you had any experiments
with corporations taking this

1038
00:56:23,040 --> 00:56:25,666
on [INAUDIBLE]?

1039
00:56:25,666 --> 00:56:27,040
DAVID J. MALAN: Not on scale yet.

1040
00:56:27,040 --> 00:56:29,410
We've been chatting with some
friends about doing this.

1041
00:56:29,410 --> 00:56:32,080
And it has certainly happened
organically with a few folks

1042
00:56:32,080 --> 00:56:32,809
here and there.

1043
00:56:32,809 --> 00:56:35,350
But we've just begun chatting
with some of our larger friends

1044
00:56:35,350 --> 00:56:36,490
in industry to do this.

1045
00:56:36,490 --> 00:56:40,210
Particularly because we have so many
alumni in some of the larger tech

1046
00:56:40,210 --> 00:56:44,290
companies in the world that we have that
built-in support structure potentially

1047
00:56:44,290 --> 00:56:45,700
among the volunteers there.

1048
00:56:45,700 --> 00:56:47,435
So we'll likely see that happen soon.

1049
00:56:47,435 --> 00:56:48,310
AUDIENCE: [INAUDIBLE]

1050
00:56:48,310 --> 00:56:49,526
DAVID J. MALAN: Indeed.

1051
00:56:49,526 --> 00:56:50,732
AUDIENCE: [INAUDIBLE]

1052
00:56:50,732 --> 00:56:51,856
DAVID J. MALAN: Oh, please.

1053
00:56:51,856 --> 00:56:57,808
AUDIENCE: Do you define comfort
zone as something that is easy

1054
00:56:57,808 --> 00:57:02,535
or something that is quickly executed?

1055
00:57:02,535 --> 00:57:07,700
And is there a further zone
which is [INAUDIBLE] people who

1056
00:57:07,700 --> 00:57:12,777
execute what you expect them to
execute, but propose something new?

1057
00:57:12,777 --> 00:57:14,360
DAVID J. MALAN: Definitely the latter.

1058
00:57:14,360 --> 00:57:17,640
When we talk about comfort zones,
less comfortable, more comfortable,

1059
00:57:17,640 --> 00:57:21,430
and somewhere in between, we actually
don't define this very precisely.

1060
00:57:21,430 --> 00:57:24,450
The rule of thumb we
offer to students is

1061
00:57:24,450 --> 00:57:27,900
that if you're a little unsure
why you're sitting in this room,

1062
00:57:27,900 --> 00:57:31,470
if you've never really had an interest
in computer science, you are, odds are,

1063
00:57:31,470 --> 00:57:32,790
among those less comfortable.

1064
00:57:32,790 --> 00:57:35,727
Doesn't mean you don't
do as well in school.

1065
00:57:35,727 --> 00:57:37,560
It doesn't mean that
you can't do the class.

1066
00:57:37,560 --> 00:57:41,919
You're just a little out of your comfort
zone, as so many students in CS50 are.

1067
00:57:41,919 --> 00:57:43,710
The more comfortable
students may very well

1068
00:57:43,710 --> 00:57:46,860
be those kids who have been programming
since they were six years old

1069
00:57:46,860 --> 00:57:48,900
and for which it might
be a lot of review.

1070
00:57:48,900 --> 00:57:52,480
And so what we try to do is treat those
demographics a little differently.

1071
00:57:52,480 --> 00:57:54,990
They still get the same
overarching experience.

1072
00:57:54,990 --> 00:57:57,220
But we encourage the teaching
fellows, for instance,

1073
00:57:57,220 --> 00:58:00,030
in the more comfortable sections,
talk about whatever you want.

1074
00:58:00,030 --> 00:58:03,340
Ask the students where it is,
what direction they want to go.

1075
00:58:03,340 --> 00:58:06,930
But with the less comfortable students,
most important is not even the material

1076
00:58:06,930 --> 00:58:11,280
being covered, but the fact that the
rest of the students in that room

1077
00:58:11,280 --> 00:58:15,450
are on the same page as them and they're
all sort of equally in that same boat.

1078
00:58:15,450 --> 00:58:19,418
And that's the extent to which we
characterize those comfort zones.

1079
00:58:19,418 --> 00:58:22,624
AUDIENCE: And getting out of the
comfort zone altogether, I mean,

1080
00:58:22,624 --> 00:58:24,200
is that a different level?

1081
00:58:24,200 --> 00:58:27,180
DAVID J. MALAN: Well, the sort
of endgame and the reassurance

1082
00:58:27,180 --> 00:58:33,090
we offer-- at the end of the semester
my email is almost always, all of you

1083
00:58:33,090 --> 00:58:36,490
are now more comfortable
than you were previously.

1084
00:58:36,490 --> 00:58:40,350
And the reality is it doesn't mean
we equalize everyone and put everyone

1085
00:58:40,350 --> 00:58:43,520
on the same footing just after three
months or six months or the like,

1086
00:58:43,520 --> 00:58:44,850
but that there's this delta.

1087
00:58:44,850 --> 00:58:49,170
And hopefully the delta is somewhat
invariant across those demographics.

1088
00:58:49,170 --> 00:58:54,450
They're just going from
one level to a next.

1089
00:58:54,450 --> 00:58:55,480
Any final questions?

1090
00:58:55,480 --> 00:58:56,255
Here.

1091
00:58:56,255 --> 00:58:59,742
AUDIENCE: [INAUDIBLE] what's
your recommendation for teachers

1092
00:58:59,742 --> 00:59:02,030
to improve their skills [INAUDIBLE]?

1093
00:59:02,030 --> 00:59:14,550
We've seen how in other
countries [INAUDIBLE]

1094
00:59:14,550 --> 00:59:15,790
DAVID J. MALAN: Yeah.

1095
00:59:15,790 --> 00:59:17,270
How do you get better at teaching?

1096
00:59:17,270 --> 00:59:19,600
So I would say at least three things.

1097
00:59:19,600 --> 00:59:20,890
Practice, first and foremost.

1098
00:59:20,890 --> 00:59:23,170
But that's an easy one to say.

1099
00:59:23,170 --> 00:59:24,910
Two is to observe.

1100
00:59:24,910 --> 00:59:29,460
Literally everything I did wrong today,
remember, and don't do that again,

1101
00:59:29,460 --> 00:59:31,269
whatever that was in your mind.

1102
00:59:31,269 --> 00:59:32,560
And I'm actually quite serious.

1103
00:59:32,560 --> 00:59:34,900
Because at least in
college and high school,

1104
00:59:34,900 --> 00:59:37,900
I certainly remember a few teachers
who I thought were amazing.

1105
00:59:37,900 --> 00:59:40,830
But I also remember a lot of
teachers who were not very good.

1106
00:59:40,830 --> 00:59:43,120
And that stuck with
me, because it gave me

1107
00:59:43,120 --> 00:59:45,250
kind of a roadmap of things not to do.

1108
00:59:45,250 --> 00:59:48,677
Like don't teach like this,
talking at the board constantly

1109
00:59:48,677 --> 00:59:50,260
while students are sort of zoning out.

1110
00:59:50,260 --> 00:59:51,580
And it's somewhat easy things.

1111
00:59:51,580 --> 00:59:54,390
But unless you keep those
in mind, you, yourself,

1112
00:59:54,390 --> 00:59:57,490
as a new teacher might fall
into those same kinds of habits.

1113
00:59:57,490 --> 01:00:00,160
So keep an eye out both for
the good and for the bad.

1114
01:00:00,160 --> 01:00:01,900
And then lastly, and
thanks to technology

1115
01:00:01,900 --> 01:00:04,534
this is just getting easier
and easier, record yourself.

1116
01:00:04,534 --> 01:00:06,700
It can be a friend standing
in the back of the room.

1117
01:00:06,700 --> 01:00:09,730
You can get a little tripod
or sort of a spider thing

1118
01:00:09,730 --> 01:00:12,910
and just prop up your phone so
that you can watch yourself after.

1119
01:00:12,910 --> 01:00:17,620
The first year I taught formally,
some 20 or so years ago,

1120
01:00:17,620 --> 01:00:19,420
every class was recorded.

1121
01:00:19,420 --> 01:00:23,190
And I painfully watched back,
like, two hours after class.

1122
01:00:23,190 --> 01:00:26,780
It was on VHS tape at the time, so I
could literally take the tape with me

1123
01:00:26,780 --> 01:00:28,480
and give it to no one else.

1124
01:00:28,480 --> 01:00:31,310
But I could watch the
tape painfully afterward.

1125
01:00:31,310 --> 01:00:33,400
And I eliminated lots of bad habits.

1126
01:00:33,400 --> 01:00:35,560
I found myself saying
the word et cetera a lot.

1127
01:00:35,560 --> 01:00:38,410
Or any time you say um or
something like that, you

1128
01:00:38,410 --> 01:00:40,150
start to hear it and notice it.

1129
01:00:40,150 --> 01:00:42,700
And nowadays I can't watch myself.

1130
01:00:42,700 --> 01:00:44,060
It's just too painful.

1131
01:00:44,060 --> 01:00:48,670
But initially that really helps, because
you see yourself through others' eyes.

1132
01:00:48,670 --> 01:00:50,500
And all three of those
techniques, I think,

1133
01:00:50,500 --> 01:00:54,723
really improve the odds of success
in being in front of the class too.

1134
01:00:54,723 --> 01:00:55,222
Please.

1135
01:00:55,222 --> 01:00:59,590
AUDIENCE: Do you have a way for
companies to get involved [INAUDIBLE]??

1136
01:00:59,590 --> 01:01:01,240
DAVID J. MALAN: We do.

1137
01:01:01,240 --> 01:01:03,460
Do we have ways of getting
companies involved too?

1138
01:01:03,460 --> 01:01:08,260
Many of the non-academic
experiences we have in CS50,

1139
01:01:08,260 --> 01:01:11,770
so to speak, like the hackathon
and the CS50 Fair and Puzzle

1140
01:01:11,770 --> 01:01:14,290
Day, which aren't sort of
core material that's created,

1141
01:01:14,290 --> 01:01:17,290
we often reach out to
friends in industry.

1142
01:01:17,290 --> 01:01:19,780
Sometimes new companies that
we don't know anyone at,

1143
01:01:19,780 --> 01:01:22,664
we just do a cold call or
send an email to someone

1144
01:01:22,664 --> 01:01:25,330
to see if they'd like to get
involved, either with sponsorship--

1145
01:01:25,330 --> 01:01:27,550
could you supply the
pizza for this event?

1146
01:01:27,550 --> 01:01:31,990
Or could you give us free copies of
some piece of software for students

1147
01:01:31,990 --> 01:01:33,520
to use for their final project?

1148
01:01:33,520 --> 01:01:36,100
Or hardware.

1149
01:01:36,100 --> 01:01:40,420
Could you send us a Microsoft HoloLens
for students to experiment with?

1150
01:01:40,420 --> 01:01:41,380
And so absolutely.

1151
01:01:41,380 --> 01:01:44,230
We have any number of ways
to get companies involved

1152
01:01:44,230 --> 01:01:46,840
so that we can do things
that we couldn't otherwise do

1153
01:01:46,840 --> 01:01:49,900
and we can provide students
with tools and hardware

1154
01:01:49,900 --> 01:01:53,780
that they might not otherwise have
access to, perhaps not even for years.

1155
01:01:53,780 --> 01:01:54,280
Here.

1156
01:01:54,280 --> 01:01:55,370
[INAUDIBLE]

1157
01:01:55,370 --> 01:02:00,575
AUDIENCE: How do you compare your
role that [INAUDIBLE] here as opposed

1158
01:02:00,575 --> 01:02:02,700
to other organizations
around the world that you're

1159
01:02:02,700 --> 01:02:04,739
working with to promote CS50?

1160
01:02:04,739 --> 01:02:06,280
DAVID J. MALAN: Can you say it again?

1161
01:02:06,280 --> 01:02:06,580
What

1162
01:02:06,580 --> 01:02:08,496
AUDIENCE: Yeah, like,
do you compare your role

1163
01:02:08,496 --> 01:02:11,480
that this institution is
playing to promote CS50 here

1164
01:02:11,480 --> 01:02:12,964
with other institutions?

1165
01:02:12,964 --> 01:02:15,130
DAVID J. MALAN: I think the
consensus among our team

1166
01:02:15,130 --> 01:02:20,405
both over the past few months and
even this week has been the [SPANISH]

1167
01:02:20,405 --> 01:02:22,480
and the school are so
much more involved,

1168
01:02:22,480 --> 01:02:24,310
I think, than a lot
of our collaborators,

1169
01:02:24,310 --> 01:02:26,410
which is a wonderful, wonderful thing.

1170
01:02:26,410 --> 01:02:30,730
For instance, at UCL, University College
London, it's completely unofficial.

1171
01:02:30,730 --> 01:02:34,120
The students there haven't really gotten
the traction with the administration

1172
01:02:34,120 --> 01:02:37,750
to give students credit, for instance,
or to secure the beautiful spaces

1173
01:02:37,750 --> 01:02:39,460
that you have around the corner here.

1174
01:02:39,460 --> 01:02:43,870
Whereas here it seems like there's
a much more cohesive collaboration

1175
01:02:43,870 --> 01:02:48,040
among these various entities, students
and faculty and foundation alike.

1176
01:02:48,040 --> 01:02:51,807
So I think that's huge to enabling
the requisite support structure.

1177
01:02:51,807 --> 01:02:53,890
But some of these opportunities
are just starting.

1178
01:02:53,890 --> 01:02:56,500
And frankly, it's like the
young lady's question in back.

1179
01:02:56,500 --> 01:02:59,451
This is how exactly things
begin in a nutshell.

1180
01:02:59,451 --> 01:03:01,450
And I think you're already
on your way to having

1181
01:03:01,450 --> 01:03:03,920
one of the most robust
opportunities for students today.

1182
01:03:03,920 --> 01:03:06,610
It's very comparable, for
instance, to Miami Dade College

1183
01:03:06,610 --> 01:03:09,610
where we had an extraordinary
friend stand something up himself

1184
01:03:09,610 --> 01:03:11,777
there as well.

1185
01:03:11,777 --> 01:03:14,711
Yeah.

1186
01:03:14,711 --> 01:03:24,744
AUDIENCE: The millennials are
now fully fluent [INAUDIBLE]

1187
01:03:24,744 --> 01:03:27,080
work their way up the curve less so.

1188
01:03:27,080 --> 01:03:32,080
Is there a difference in that in
terms of the ability [INAUDIBLE]??

1189
01:03:32,080 --> 01:03:35,380
DAVID J. MALAN: So millennials are
very comfortable with technology,

1190
01:03:35,380 --> 01:03:37,390
with the latest technologies and apps.

1191
01:03:37,390 --> 01:03:40,180
And perhaps as your older, less so.

1192
01:03:40,180 --> 01:03:43,510
I think it's been important
for us to stay abreast of this.

1193
01:03:43,510 --> 01:03:45,490
And I say this somewhat hypocritically.

1194
01:03:45,490 --> 01:03:48,280
Because I'm told that Rick
Rolls are not in vogue anymore,

1195
01:03:48,280 --> 01:03:52,690
but you'll see throughout CS50 such
things as that, if you're familiar.

1196
01:03:52,690 --> 01:03:55,750
But yes, we have been very
conscious of technology

1197
01:03:55,750 --> 01:03:58,960
students are using, not just so
that we have a presence there.

1198
01:03:58,960 --> 01:04:01,060
I mean, we do have a CS50 Snapchat.

1199
01:04:01,060 --> 01:04:03,530
We have Snapchat filters
when we hold events,

1200
01:04:03,530 --> 01:04:05,530
for instance, just for
students to use for fun.

1201
01:04:05,530 --> 01:04:07,600
But we also use these
new trends and apps

1202
01:04:07,600 --> 01:04:10,720
as opportunities for
teaching teachable moments.

1203
01:04:10,720 --> 01:04:13,780
Like, we'll email our friends at
Snapchat or some other company

1204
01:04:13,780 --> 01:04:15,939
to come talk about how
it is their app works.

1205
01:04:15,939 --> 01:04:18,730
And when a message gets deleted,
what does that mean, for instance.

1206
01:04:18,730 --> 01:04:20,480
That would be an opportunity there.

1207
01:04:20,480 --> 01:04:22,900
So I would say we tend to
use the latest technologies

1208
01:04:22,900 --> 01:04:25,480
and tools as an opportunity
to really weave them

1209
01:04:25,480 --> 01:04:26,890
into the fabric of the course.

1210
01:04:26,890 --> 01:04:29,140
And I mentioned a HoloLens
just a moment ago.

1211
01:04:29,140 --> 01:04:31,556
That was a piece of hardware
that a couple of our students

1212
01:04:31,556 --> 01:04:35,890
actually used for their final projects
after just three months of taking CS50.

1213
01:04:35,890 --> 01:04:40,870
And we had similar explorations with VR,
with Samsung Gear, and with HTC Vive,

1214
01:04:40,870 --> 01:04:42,194
and other such technologies.

1215
01:04:42,194 --> 01:04:44,110
So we've stayed abreast
of these, particularly

1216
01:04:44,110 --> 01:04:47,830
to equip students with them, not
as a senior capstone project,

1217
01:04:47,830 --> 01:04:52,212
but really as a first year introduction.

1218
01:04:52,212 --> 01:04:53,920
We have time for a
couple more questions.

1219
01:04:53,920 --> 01:04:54,622
Yeah.

1220
01:04:54,622 --> 01:04:57,996
AUDIENCE: [SPEAKING SPANISH]

1221
01:04:57,996 --> 01:05:02,380
DAVID J. MALAN: [SPEAKING SPANISH]

1222
01:05:02,380 --> 01:05:05,080
AUDIENCE: [SPEAKING SPANISH]

1223
01:05:05,080 --> 01:05:07,010
DAVID J. MALAN: [SPEAKING SPANISH]

1224
01:05:07,010 --> 01:05:10,510
AUDIENCE: [SPEAKING SPANISH]

1225
01:05:10,510 --> 01:06:13,942


1226
01:06:13,942 --> 01:06:16,150
DAVID J. MALAN: Let's hope
Christian has good memory.

1227
01:06:16,150 --> 01:06:19,120


1228
01:06:19,120 --> 01:06:22,585
CHRISTIAN: So in today's world with
technology being so present everywhere,

1229
01:06:22,585 --> 01:06:29,020
do you see technology as the main
tool for improving education?

1230
01:06:29,020 --> 01:06:32,980
And are there any differences
in the US and here?

1231
01:06:32,980 --> 01:06:36,490
But how is technology the right tool?

1232
01:06:36,490 --> 01:06:38,320
DAVID J. MALAN: [SPEAKING SPANISH]

1233
01:06:38,320 --> 01:06:39,550
So I think it's enabling.

1234
01:06:39,550 --> 01:06:43,720
I certainly don't think technology is
the solution to educational problems.

1235
01:06:43,720 --> 01:06:48,940
And I remember back when I was a
younger student in middle school

1236
01:06:48,940 --> 01:06:53,590
where they were giving every student
in the school a laptop just because.

1237
01:06:53,590 --> 01:06:56,590
And it was as though the mere
introduction of technology,

1238
01:06:56,590 --> 01:06:59,110
in that case, laptops back
in the day, was somehow

1239
01:06:59,110 --> 01:07:00,850
going to improve their experience.

1240
01:07:00,850 --> 01:07:04,480
But what they failed to do, and even
years later when I taught high school--

1241
01:07:04,480 --> 01:07:09,050
I taught high school math-- and every
classroom in my school had a computer.

1242
01:07:09,050 --> 01:07:11,600
They didn't teach any of the
teachers what to do with it.

1243
01:07:11,600 --> 01:07:13,450
They didn't provide
them with the training.

1244
01:07:13,450 --> 01:07:17,590
They didn't provide them with useful,
compelling pieces of software.

1245
01:07:17,590 --> 01:07:19,420
And I think that's what's key.

1246
01:07:19,420 --> 01:07:22,877
What's far more important
is the human factor.

1247
01:07:22,877 --> 01:07:24,460
And you're seeing it again these days.

1248
01:07:24,460 --> 01:07:28,390
Schools having iPads for everyone, for
instance, especially at younger levels.

1249
01:07:28,390 --> 01:07:31,060
But unless you have the
right software and you

1250
01:07:31,060 --> 01:07:34,090
have the right use cases
in mind, I don't think

1251
01:07:34,090 --> 01:07:36,460
that technology alone is the solution.

1252
01:07:36,460 --> 01:07:43,910
It's simply enabling humans to
do a better job in, for instance,

1253
01:07:43,910 --> 01:07:46,790
the classroom.

1254
01:07:46,790 --> 01:07:48,000
Maybe two questions more.

1255
01:07:48,000 --> 01:07:48,778
Over here.

1256
01:07:48,778 --> 01:07:51,152
AUDIENCE: First of all, thank
you so much for being here.

1257
01:07:51,152 --> 01:07:53,588
[INAUDIBLE]

1258
01:07:53,588 --> 01:07:54,588
DAVID J. MALAN: De nada.

1259
01:07:54,588 --> 01:07:57,576


1260
01:07:57,576 --> 01:08:03,552
AUDIENCE: [INAUDIBLE] what
would be the next step?

1261
01:08:03,552 --> 01:08:06,865
What would be [INAUDIBLE]?

1262
01:08:06,865 --> 01:08:08,490
DAVID J. MALAN: A really good question.

1263
01:08:08,490 --> 01:08:11,900
After taking CS50, what would
be the next class to take?

1264
01:08:11,900 --> 01:08:14,750
And We were just having this
conversation, some of us, earlier.

1265
01:08:14,750 --> 01:08:17,490
CS50 itself is in the
process of beginning

1266
01:08:17,490 --> 01:08:21,870
to create follow-on materials
that are more technical,

1267
01:08:21,870 --> 01:08:24,727
are more technology specific.

1268
01:08:24,727 --> 01:08:25,560
We're not there yet.

1269
01:08:25,560 --> 01:08:27,310
But there soon will
be those opportunities

1270
01:08:27,310 --> 01:08:30,729
that you'll see within
edX and elsewhere online.

1271
01:08:30,729 --> 01:08:36,240
But for now it is a wonderful thing
that Coursera and edX and Udacity

1272
01:08:36,240 --> 01:08:39,029
and not to mention YouTube
and iTunes University,

1273
01:08:39,029 --> 01:08:43,439
there are so many places to get
high quality educational content.

1274
01:08:43,439 --> 01:08:47,430
I'll often point students to a
algorithms and data structures class

1275
01:08:47,430 --> 01:08:51,630
from Princeton, which is
freely available on Coursera

1276
01:08:51,630 --> 01:08:53,313
from some colleagues there.

1277
01:08:53,313 --> 01:08:55,229
And beyond that, I would
encourage you to find

1278
01:08:55,229 --> 01:08:56,729
courses that are of interest to you.

1279
01:08:56,729 --> 01:09:00,750
If you like software engineering and
maybe iPhone programming or Android,

1280
01:09:00,750 --> 01:09:03,540
Stanford, for instance, is how
I learned iPhone programming.

1281
01:09:03,540 --> 01:09:07,210
Years ago they had a freely available
course that was very popular.

1282
01:09:07,210 --> 01:09:10,080
And so I just reached out
to that course for free.

1283
01:09:10,080 --> 01:09:13,920
So I would decide based on what you see
in the menu on these various websites

1284
01:09:13,920 --> 01:09:14,970
what might interest you.

1285
01:09:14,970 --> 01:09:17,670
And to your classmate's
suggestion earlier,

1286
01:09:17,670 --> 01:09:20,417
find a friend or a set of friends
to perhaps do it with you.

1287
01:09:20,417 --> 01:09:22,500
Because I think that only
improves the probability

1288
01:09:22,500 --> 01:09:24,416
if you sort of put some
pressure on each other

1289
01:09:24,416 --> 01:09:28,350
and help answer questions for
each other, succeeding in the end.

1290
01:09:28,350 --> 01:09:29,520
AUDIENCE: [INAUDIBLE]

1291
01:09:29,520 --> 01:09:32,035
DAVID J. MALAN: Oh, sure.

1292
01:09:32,035 --> 01:09:34,415
AUDIENCE: Have you identified
any special talents

1293
01:09:34,415 --> 01:09:37,032
through courses like those on edX?

1294
01:09:37,032 --> 01:09:38,657
DAVID J. MALAN: Have we identified any?

1295
01:09:38,657 --> 01:09:39,970
AUDIENCE: Prodigies.

1296
01:09:39,970 --> 01:09:41,450
DAVID J. MALAN: Oh, prodigies.

1297
01:09:41,450 --> 01:09:45,689
Presley, the 11-year-old, has a very
good start on some of the students

1298
01:09:45,689 --> 01:09:46,500
thus far.

1299
01:09:46,500 --> 01:09:48,029
So we have to some extent.

1300
01:09:48,029 --> 01:09:51,149
We Have a fellow whose
name is Kareem who

1301
01:09:51,149 --> 01:09:55,050
lives in Cairo, Egypt, who kind
of came on our radar thanks

1302
01:09:55,050 --> 01:09:59,460
to Facebook and Stack Exchange,
both of where he was very active.

1303
01:09:59,460 --> 01:10:03,130
And actually he has a visa appointment
in just a few days with the embassy

1304
01:10:03,130 --> 01:10:03,630
there.

1305
01:10:03,630 --> 01:10:06,840
And then hopefully next week he'll
be moving to Cambridge, Massachusetts

1306
01:10:06,840 --> 01:10:08,130
to join us full-time.

1307
01:10:08,130 --> 01:10:11,010
Arturo Real, who I mentioned
earlier from Venezuela and Miami,

1308
01:10:11,010 --> 01:10:13,440
he joined us about a year ago.

1309
01:10:13,440 --> 01:10:16,290
Christian here, who's been
helping out, came from Guatemala

1310
01:10:16,290 --> 01:10:20,430
and wanted to actually stand up his
own local opportunity for students

1311
01:10:20,430 --> 01:10:23,347
and we kind of stole him away for a
year to come to Cambridge as well.

1312
01:10:23,347 --> 01:10:26,263
AUDIENCE: [INAUDIBLE] about vertically
integrated with all the systems

1313
01:10:26,263 --> 01:10:27,420
you have to deliver it in?

1314
01:10:27,420 --> 01:10:27,885
DAVID J. MALAN: We are.

1315
01:10:27,885 --> 01:10:28,560
We are.

1316
01:10:28,560 --> 01:10:30,960
And to that same point of
integration, nowadays when we

1317
01:10:30,960 --> 01:10:33,900
have a CS50 Fair at
Harvard or at Yale, we

1318
01:10:33,900 --> 01:10:37,110
invite hundreds of our CS50
AP high school students

1319
01:10:37,110 --> 01:10:39,570
to come to those events,
so that hopefully it's

1320
01:10:39,570 --> 01:10:41,790
an opportunity for a bit of inspiration.

1321
01:10:41,790 --> 01:10:45,870
And hopefully it's all the more
opportunities for our university

1322
01:10:45,870 --> 01:10:48,180
students to talk with
those younger students who

1323
01:10:48,180 --> 01:10:52,760
are genuinely interested in
what it is they have done.

1324
01:10:52,760 --> 01:10:54,510
Well, allow me to
officially adjourn here.

1325
01:10:54,510 --> 01:10:57,460
But I'm happy to stick around with the
whole team for additional questions.

1326
01:10:57,460 --> 01:10:58,626
But it's been such an honor.

1327
01:10:58,626 --> 01:10:59,900
[SPEAKING SPANISH]

1328
01:10:59,900 --> 01:11:01,750
[APPLAUSE]

1329
01:11:01,750 --> 01:11:03,616