"Everytime you don't show your work, God kills a kitten."
He also kills them you don't draw a graph. Some responses James from the Forum had on papers when he let some underaged alcoholics grade his papers (Kevin Omega and Mikey).

Some others:

Evil James: I warn you now. For these homework were graded by underaged alcoholics.

"Scientists have proven that doing your homework increases your chances of passing."
"Daddy drinks because you cry."
"If you didn't suck too much at math, maybe your father wouldn't have left us."
"Mommy left us because you didn't draw graphs."
"Everytime you get a math problem wrong, God kills a kitten."
"Some people should start getting stuff wrong. I'm tired of being nice."
"Help! I'm trapped in an under-grad T.A.'s mine. Please tell my wife...oh no! They've spotted me."
"What? Only a perfect score? Go to your room and assume the position."
"I'm the Lorax. I speak for the trees."
"You're like dead fish floating in the sea of life. Too busy floating up-side-down to do your homework."
"Oh look! You got a grade. Good job."
"I don't get math. Couldn't you have written an essay about your dog. I'd have an easy time grading it."
"Was it as good for you as it was for me?"