Here's another great one: a certain well known mathematican, we'll call him Professor P.T. (these are not his initials...), upon his arrival at Harvard University, was scheduled to teach Math 1a (the first semester of freshman calculus.)
He asked his fellow faculty members what he was supposed to teach in this course, and they told him: limits, continuity, differentiability, and a little bit of indefinite integration.
The next day he came back and asked, "What am I supposed to cover in the second lecture?""
The funny thing about this is that we covered all of that in a total of 6 hours (2 hours per day) during my first year in CPGE.
