Here’s what Mazur has figured out about what goes on when the students talk with each other during peer instruction:
“Imagine two students sitting next to one another, Mary and John. Mary has the right answer because she understands it. John does not. Mary’s more likely, on average, to convince John than the other way around because she has the right reasoning.”
But here’s the irony. “Mary is more likely to convince John than professor Mazur in front of the class,” Mazur says.
“She’s only recently learned it and still has some feeling for the conceptual difficulties that she has whereas professor Mazur learned [the idea] such a long time ago that he can no longer understand why somebody has difficulty grasping it.”
That’s the irony of becoming an expert in your field, Mazur says. “It becomes not easier to teach, it becomes harder to teach because you’re unaware of the conceptual difficulties of a beginning learner.”