I think I remember this one. It took place in a school classroom. Professor Grover was talking about school, but he really didn't know anything, so the students corrected him. For example, he said the people in the classroom were called 'customers,' then everybody said "No, they're called 'students.'" Anyway, I guess the Muppet's in this sketch were Grover and the students. I don't recall the ending music though. Overall, I felt it was a good sketch.