Nothing too hilarious. 
Sorry if you've seen variants of these little tidbits but the first really happened:

When a thief found there was too little money in an Oklahoma convenience store, he bound up the cashier. He was caught when the police arrived to find him attending the register himself.

"When George Washington chopped down his father's cherry tree, he admitted doing it. Now do you know why his father didn't punish him?"asked the teacher.
The student responded, "Because he still had the ax in his hand."

"I don't think I could accumulate that much dirt if I lived two more lifetimes. How did you get so dirty, Johnny?"
"Well, Mom, I'm much closer to the ground than you are."