A kid walks into a class with a shirt, pants, underwear, and socks the teacher asks, "Where have you been?" The boy says, "On top of blueberry hill."

Then another boy walks in with no shirt and no socks and the teacher says, "Where have you been?" The boy says, "On top of blueberry hill."

Then a girl walks in and the teacher asks, "Where have you been? Oh, let me guess on top of blueberry hill." and the girl says, "No, I am blueberry hill."