A young man, the first of his family to ever attend school, was sitting at his desk doing his homework. His father came up behind him, studied the papers for a moment, and then said, "Well, son, how do you like school?" "Oh, I like it fine." the boy replied. "Guess what we learned today? Pi r squared."
The father frowned deeply and said "What kind of thing is that to teach children? Everyone knows that pie are not squared, pie are round!"