Bart the Genius

Season 1, Episode 2

To get back at class nerd/teacher's pet, Martin Prince, for ratting him out to Principal Skinner for vandalism on school property, Bart switches his own intelligence test with Martin's. During a parent/principal conference about the defaced wall, the school counselor, Dr. Pryor, announces that Bart is a genius and only acts out because public school isn't stimulating enough, so Bart is sent to a school for genius kids — and finds out just how painfully below average he is.