DAVID MALAN: --less on the lower level implementation
details of code, that we'll look at a couple of examples.
So this more--
DOUG LLOYD: Go ahead.
DAVID MALAN: I was going to say, more than a couple of examples.
This is actually one of the heaviest visual lectures that we have,
with lots of demonstration.
DOUG LLOYD: Yeah, if you take a look at the syllabus at a high level,
there's a lot of topics that we cover.
We spend almost an entire lecture in week three
just talking about different algorithms.
We're going to going to solve the same problem many different times, just
using a number of different algorithms.
DAVID MALAN: Yeah, and I actually worry that I throw too much of the kitchen
sink at this one, it's fun I think to involve students as much as we can,
and the reality is, especially now that this year's lectures are
fewer but longer, they sort of naturally all fit
within the same units of lecture.
But I think for other teachers, especially in high schools and colleges
elsewhere, like cherry picking some of these topics is good.
And I think probably I should be cherry picking as well,
and not using every example every year, but it's
kind of hard to make the trade off I think.
DOUG LLOYD: When we have demonstrations of sorting numbers on stage
or sorting people on stage, eventually we're
going to find out that bubble sort, and insertion sort selection,
that they're all 0 of n squared algorithms, they're all the same.
But the way they look is really different,
and I don't think you can appreciate that
without seeing a physical representation of those--
DAVID MALAN: Yeah, I agree.
DOUG LLOYD: --differences.
DAVID MALAN: And this one used to be very physical,
so our touchscreen implementation is the more modern incarnation
of what used to be just a chalkboard where I would use tape and paper,
and paper the board with like eight pieces of paper behind which
I would draw with chalk some numbers and have stood and search
for those numbers.
DOUG LLOYD: And if memory serves, that might
be one of the most memorable moments we've ever had in CS50 actually.
DAVID MALAN: Yes, [? Sean, ?] bless his heart struggled so to find
the number he was searching for.
But it was good because it lends themselves to these memorable moments,
right?
Like he and a lot of his classmates will never
forget the time that he was trying to inefficiently search for numbers
behind a door, especially inefficiently in his case
as we'll eventually see here.
DOUG LLOYD: It make the class a lot more fun.
It draws people in sometimes when things don't go well.
It's kind of funny to have things go off the rails a little bit
as long as you can hopefully get it back where it's supposed to be.
I mean this is great, it gives us an opportunity to talk about sorting
and how sorted lists--
you can search them eventually more efficiently as we're going to see now.
I think it's good to all these demonstrations
and get people involved and physically seeing where these things are going.
DAVID MALAN: But there's a trade, I mean we
know from mid and end of semester evaluations and feedback forms
from students that there are some students who really
don't like that we get mired in some of these longer form demonstrations,
right.
For the student for whom binary search, linear search, and all of this
comes very quickly, very naturally, they don't
need to be a captive audience member in a space like this.
But this is why I think it's so much more
effective being able to engage with the course's content online in the video,
especially now that we have a table of contents
and you can very easily jump to other sections.
If you get this and fun though it may be you want to skip this,
it's just all the easier and you don't even manually scrub and find
the next spot, you can just jump over, leapfrog this whole section entirely.
And so that's what helped this year, I was much more comfortable
with the kitchen sink in doing all of these demonstrations knowing
that now everything is wonderfully indexed thanks to Colton and Luke's
video player, and we can very quickly jump around, or the student can,
to what topics they actually do want to spend time on.
DOUG LLOYD: There's something else you mentioned in that description earlier,
which is these feedback forms that we actually
collect at the end of every assignment, I think some people might not realize,
we actually do take these things really seriously
and at the end of every semester you, and I,
and other members of the senior staff really
sit down and process all of this.
DAVID MALAN: A huge amount.
DOUG LLOYD: And this year your particular
it became really noticeable with our switch to Python,
and the way we deliver lectures, but you know,
we're constantly trying to improve our own delivery of content [INAUDIBLE]
as well.
DAVID MALAN: Yeah, this year was a big change.
Certainly the lecture times and frequencies was just the least of it,
so much curricularly has changed and structurally about the class.
Certainly.