SPEAKER: This is CS50.

DAVID MALAN: Hello, world.

This is the CS50 podcast.

My name is David Malan.

BRIAN YU: My name is Brian Yu.

And today, we thought we'd talk a little bit about the CS50 Fair, which

takes place at the end of CS50 every semester,

an opportunity for students to show off their final projects.

I've been to, what is it now, five CS50 Fairs, I think.

Now, how many CS50 Fairs have there been?

DAVID MALAN: There have been 12, and I have been to all 12 of them.

BRIAN YU: All right.

What was the first one like?

DAVID MALAN: The first one was similar in spirit to what you see now,

if any of you listening online have seen any of the photographs or video footage

from them.

But it was smaller scale.

BRIAN YU: Was this the first year that you taught the class,

or does it come about later?

DAVID MALAN: This was second year.

So this was in 2008, when we had 287 students in the class.

So it was a smaller scale event.

We divided it into just a couple-- two or three shifts of students,

with maybe 100 or so students, give or take,

presenting their final projects at any one time.

But it was in our original space on campus, the building of a basement

called Northwest Science, which is one of the science buildings on campus,

with a big concrete floor area, lots of tall ceilings and pillars

that we were able to set up a whole lot of tables

on for students to present their final projects.

BRIAN YU: And the CS50 Fair now-- especially for people

who've seen it online, probably have seen photos of what it looks like now.

It's fancy.

There are balloons.

There's high tables with nice tablecloths all over it.

Was it like that from the beginning, or what was the first CS50 Fair

like visually?

DAVID MALAN: Yeah, it was actually-- so the whole intent of the CS50 Fair,

for those unfamiliar, is to be a course-wide and campus-wide exhibition,

if not celebration of students' final projects in the course.

In a nutshell, for CS50, our undergraduate course

in computer science, students can implement most

any software-based project of interest to them at the end of the semester.

And the goal of the CS50 Fair was to provide a vehicle

at the end of the semester for students to present

their work to classmates, to staff, and to students, faculty, and staff

from across campus.

So yes, I worked with one of our earliest assistant head

teaching fellows, Yuki Yamashita, who was a junior or senior at the time.

And he and I pretty much spent winter break

over the phone and email planning the very first CS50 Fair.

At the time, Harvard's exams were after the break,

so the very first CS50 Fair was actually in January,

not in December, which it now is, when the course was closer to concluding.

And we pretty much knew the dimensions of the space--

the basement space of Northwest Science, big concrete floor and pillars--

and we knew the distance between all of those pillars.

And so we essentially came up with all of these estimations and models

using Photoshop or some other such tool to mock up the space.

And we knew we wanted bar-height tables.

We wanted students, and staff, and faculty to be able to walk by

and not have people seated or crouching over.

We got just very simple tablecloths to cover everything to the floor.

And then we realized we wanted to decorate the space.

And the easiest way to decorate a space, especially with tall ceilings,

is just to put some balloons with helium on string.

And so that's what we did early on to adorn the space.

BRIAN YU: And how did you figure out where

to get enough tables to have 300 people present

their projects and enough balloons to fill an entire basement of a building?

It feels like there's a lot of just upfront logistics

to figure out in terms of how to make this work.

And now we can just rely on, oh, let's do what we do last year.

But the first time must have been much tougher.

DAVID MALAN: Yeah, no, we had to envision everything

off the top of our heads.

And when we-- I'm guessing we asked someone at the time,

hey, where can we get a 100 bar-height tables?

Well, Harvard doesn't have its own supply of those,

and so there's a local place that we ultimately had to rent them from.

The tablecloths as well.

We knew way too much about the per-unit cost of tablecloths and tables

at the time.

But we also, from that same vendor, for instance, got a few popcorn machines.

We wanted to make it kind of like a fair,

really, like a carnival of sorts, albeit academically oriented.

So we got two or three popcorn machines, the idea

being that the teaching fellows and the staff running the event

could pop some popcorn, and it would be a nice way to say hello to people

and greet them on the way in.

I think not the first year-- eventually, we

tried cotton candy machines, which is so much fun to make,

because you finally understand how it works by putting a little paper cone

'round and 'round in the sugar.

But oh my god, what a mess it makes.

You don't really want free-flowing sugar in the air,

so we killed that after a while.

BRIAN YU: The popcorn machines aren't easy to use.

I remember struggling to figure out how to actually make popcorn in the popcorn

machine the very first time, because I'd never actually used

a popcorn machine before.

DAVID MALAN: Yeah, no.

There's the big carnival-style ones or that you'd get from a vendor

off the street.

So secretly, in recent years, we've started pre-buying the popcorn

in really big boxes--

BRIAN YU: [CHUCKLES] Makes things a lot easier.

DAVID MALAN: --just like the movie theaters do,

but we put it out on display in boxes.

But we actually really did very nitpickily think

about all of the low-level details.

We had-- even the popcorn boxes, we wanted to make sure that they were flat

and weren't just paper things, because we wanted students

to be able to put them down, and passersby put them down

while interacting with students' laptops.

I think we even had water machines, like dispensing water.

We deliberately got those conical cups that

come to a triangular point as opposed to flat bottom ones

because we wanted people literally to finish any water they had in their cup

so as to minimize the risk that someone was going to put a cup of water

down near a student's laptop and spill.

So we were even obsessing to that level of detail early on.

And while we didn't do this the first year,

we actually realized quickly that in such a large group of people,

the balloons that we first got for the first year or more of the fair

were latex.

And unfortunately, too many people are allergic to latex, potentially,

especially when you have hundreds of them floating around in the air.

So after one or more years, we switched to foil balloons,

Mylar balloons instead, which unfortunately are more expensive,

but they don't have the allergens.

BRIAN YU: Huh, that never would have ever crossed my mind.

Were there any other surprises, things you

weren't expecting that suddenly came up during the process of planning

and executing that very first fair?

DAVID MALAN: That was certainly one.

Not so many surprises, otherwise-- we eventually

realized that we don't need to worry too much about conical-shaped cups.

We eventually got flattened bottom cups.

And knock on wood, nothing bad has happened to any laptops with water.

No, I think we--

and Yuki was great at this event planning, and envisioning designs.

We introduced some very deliberate design decisions, like we had--

we wanted to invite some industry friends, and alumni,

and recruiters, really, from companies, popular tech companies that we

knew students might have an interest in working for over the summer

or full-time.

So we actually invited eight or so such folks from industry that year,

but we very deliberately put them at the back of the room.

One, we didn't want companies to be the focus of the event.

It was obviously supposed to be focused on the students,

and so a supermajority of the tables were indeed

allocated to students' laptops and their projects.

But we also very deliberately, when people came into this large space,

wanted to pull them through the whole space.

So even those upperclassmen, or say, juniors and seniors

who might be there primarily to look into job opportunities, but secondarily

wouldn't mind chatting with friends and seeing their projects and so forth.

We wanted to compel them to go through the space, see all of the projects

before they actually reached the table.

So we tried to think about details like that.

And then we did introduce the first year-- oh, yeah, this was unforeseen.

We got stress balls, which are just these squishy spherical things that

say CS50 on them, or CS50 stress ball, literally, nowadays.

And we wanted the TFs to hand them out as people came into this space,

and descended this beautiful staircase that leads into this space.

What we didn't expect was that the TFs would start throwing the stress

balls at attendees, which was actually kind of an issue,

because they don't hurt, and it's not a danger like that,

but when you're throwing the stress balls up a stairwell

and you don't necessarily have good aim, then

do the balls come back down thanks to gravity and knock things over.

So it's been hard to put downward pressure on that tradition,

but I think we finally killed it off.

BRIAN YU: Yeah, well, we've moved-- so Northwest was the original location.

That basement was the original location for the first fair.

And you stayed there for 10 years.

Is that right?

DAVID MALAN: Oh, let's call it--

10 years.

Yeah, 10 years, and then two years now in a different place.

BRIAN YU: Yeah, and so this new location, how did that come about?

So we just-- in the last two years, switched

to holding the CS50 Fair in the Smith Center, this newly-renovated part

of Harvard's campus.

Did you know immediately that's where you wanted to move the fair to,

or how did that come about?

DAVID MALAN: Yeah.

So Harvard recently renovated a building that was once called the Holyoke Center

and is now called the Smith Center.

And it's more of a community space on campus.

They gutted the first couple of floors, enlarged the ceilings,

and made this beautiful big open space called Harvard Commons, which

is a glassed-in area that has chairs, and tables, and a little stage,

and just a lot of big open space.

And the best feature of it is that it's 100% central in Harvard Square, which

is the heart of the area right next to Harvard Yard,

and whereas Northwest Science was one of these buildings on campus

that really was on the periphery, so it's a destination.

Like, you have to intend to go to the CS50 Fair,

and therefore, there's that non-zero activation energy to just get

attendees to come chat with folks.

So the fact that it's now in Harvard Square

is great, because we have all the more passersby, even tourists,

people who are just poking their head in to see what goes on at a university,

and what our students have accomplished.

And the upside of that is that there's all the more

attendees to chat up our own students and ask

them to show off their projects.

So hopefully, it's a win-win for everyone.

BRIAN YU: Yeah, that sounds like a huge advantage.

Because Northwest-- if you're unfamiliar with the layout of Harvard's campus,

if you look at a map of Harvard's campus,

Northwest is in like the far corner of the campus.

And on some maps, it's just cut off altogether.

You can't even see it.

So it is-- you do have to journey a little bit in order to get there.

What did you do in the very first year before people