Knock Knock

So traveling with two 4 year olds(lizzie and the girl I watch), I get to hear all sorts of conversation. Hear are some of the jokes they were telling. It started off okay and quickly went downhill.

Why did the cookie go to the doctor? Because he was crumby?
Knock, knock! Who's there? Scooby. Scooby who? Scooby Doo
Knock, knock! Who's there? you. You who? ha ha

After a few more "jokes" I threw in Why was 6 afraid of 7? cause 7 eight 9
the next joke was
Why was the orange afraid of the banana? because the banana had a bigger peel.
Knock, knock! Who's there? banana. Banana who? banana you glad I didn't say orange
Knock, knock! Who's there? salt. Salt who? Salt and Pepper.

Just though I would pass on these wonderful jokes. Oh, believe it or not, but I had a good bagging experience at the grocery store.