Teaching is hard, and teaching well is REALLY hard. If you’ve never done it before, you have no idea how many hours of preparation each lecture takes. The trick to counter that is to teach the same class over and over. By the n-th time you teach it, you can get away with much less preparation, but even then some of the lectures truly suck.
I teach the same class every other semester: Great Theoretical Ideas in Computer Science. If you’re a CMU undergrad, you surely have strong memories about this class (positive or negative). If you’re not, all you need to know is that it’s a discrete math course required for all computer science majors and usually has about 200 students in it. When I spend millions of hours preparing for the class, it ends up being pretty good (teaching awards, very high student evaluations, etc.) Unfortunately, some weeks I don’t have millions of hours to spend on it so the lectures are not as good as I would want them to be (and the students fall asleep!). But let’s all be honest here: even when I prepare a lot, the lectures are not all that great. I make mistakes, I forget to say some things, my handwriting is bad, my jokes fall flat, etc. Every semester there are maybe 3-4 lectures that I am happy with afterwards, and of the rest about 50% totally suck in my mind and 50% are just barely passable. The fact that I am considered one of the better teachers of the department is, truthfully, sad.
So, a good fraction of my lectures totally suck. I am also quite tired of repeating almost the same thing over and over every semester (and what sucks more is that sometimes it comes out great and sometimes it doesn’t!). So here’s my proposal: instead of my amateurish attempts at making good lectures that fail most of the time, and instead of repeating the same crap every semester like a broken record, why don’t I just produce really good video lectures?
Now, I know what you will say: “Video lectures suck! They tend to put the students to sleep even more than real life professors, the audio quality is poor, you can’t see the board, etc.” And I agree. There is just something about being there in real life that cannot be captured by a video and this makes recorded lectures be even crappier than their real life counterparts.
But I’m not talking about simply recording myself giving a regular lecture. I think that would suck. I am talking about making a high production value movie for every lecture. I’m talking about professional script writers (those guys that make the Daily Show or the Colbert Report so funny), about special effects and computer graphics to illustrate the concepts instead of the board, about high end directors, cameramen, and producers (like the guys who made my Nova special).
I’ve spoken with some of my friends in the movie industry (writers, producers and directors of Hollywood blockbusters), and they all seem quite excited about trying to do this. The biggest problem seems to be the cost. It’s hard to estimate how much each lecture would cost, and it clearly depends on how much quality you want, but it seems each lecture can be done for between $75k to $300k. If we make 30 lectures to cover the whole semester, that amounts to something between $2 million and $9 million. This type of investment is probably not worth it for higher-level classes that are only taken by a few people each semester. But for a discrete math class taken by 200 students every semester at CMU alone (and tens of thousands of students throughout the world every year), I think it’s well worth it.