Im sorry, but the no racist thing, I won't be able to follow that in some cases, so I have put the possibly mildly offensive one in spoiler.
Your mother is like school in July, no class.
Yo mama so fat, when she's at the cinema, she sits next to everyone.
The guy that came up with door knocking should get a no-bell price.
Hey, do you want some shrimp? Sorry, I'm jewish. Oh no, you don't understand, it's free!