Pop quiz question one: You have a metal plate with a hole in it. You microwave the plate. Does the hole grow, shrink, or stay the same?
Question two: If Harvard University physicist Eric Mazur lectures a class of highly intelligent students on how atoms move away from each other in response to heat, then asks them question one, how many give the wrong answer?
Most of them, it turns out, because one of the least effective ways to teach is to stand in an auditorium and deliver a monologue on facts, as Mazur did in explaining the motion of atoms. In other words: Lectures, the dominant mode of instruction in classrooms, just do not work, no matter how smart your students are.
On Friday, Mazur posed question one to a group of Harvard professors who indeed mostly got the answer wrong. Then he proceeded to show the group exactly why his lecture had been so ineffective, by teaching in a different way. (More on what he did - and on the correct answer to question one - in a bit.)