Funny Dirty Joke

A little boy named Charlie complains to his teacher, "I'm too smart for 1st grade!". The teacher then goes to the principal with Charlie. The principle first asks some questions:

3 x 3? 9
6 x 3? 18
6 squared? 36

The principal is impressed by Charlie's intelligence, and allows him to be in the 3rd grade. The teacher responds "HOLD THE DAMN PHONE!" and asks Charlie some questions.

What does a cow have 4 of that I only have 2?
Harry then says 'Legs'
What is in your pants that is not in mine?
'pockets'
What does a dog do that a man steps into?
'pants'
What goes in hard and comes out soft?
'bubble gum' (SHAME ON YOU!)
What does a man do standing up, a woman sitting down, and a dog on 3 legs?
'shake hands'
What word starts with F, has a U and C in it, and ends with a K that means heat and excitement?
'firetruck' (SHAME ON YOU!)

The Principal then says "F*ck that, he can go to 5th grade, since I got the last 7 questions wrong.

(SHAME ON YOU!)