Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.

Bean delivers the funniest line in the entire film.
Bernard: They probably cheated [on their test].
Bean: Your mom cheated; that's why you look like a plumber.
Anything Rose the Nose says, specifically:
Rose the Nose: As far as you're concerned, Dink Meeker is God.
Ender: What does that make you?
Rose the Nose: The personnel officer that hired God.
Ender roasting Bernard during the lecture at Battle School.
Ender: Bernard is proof that they still send chimps into space.

Funny / Ender's Game