I take the fifth

I told the kids in one class a fraction-related joke today.

A guy walks into a restaurant and orders a pizza.  The waiter asks if the man would like the pizza cut into 4 pieces or 8 pieces.  The man replies, "Better make it 4.  I could never eat 8 pieces!"

There were a few pained grimaces of non-understanding, and a general lack of comprehension.  When we started talking about it, how the guy would be eating the WHOLE pizza, no matter whether it was cut into 4 pieces or 8, a few kids started to get it.

One kid had his hand raised the whole time, and when I finally called on him, he asked, "How old is that joke?"

I said, "I'm not sure, but pretty old."

He then said, "Oh, no wonder it's not funny."