Blind Teacher

Alright, listen up, you smooth-brained chucklehead. This joke is all about wordplay. See, a "pupil" can mean either a student in a class or the black circle in your eye—which, by the way, probably struggles to process light at your age. Since a blind person can't see, they obviously can't "control their pupils" in the seeing sense, which is why they can't control the students.