Yo Mama - Tail

Yo mama so ugly, the last time I saw something that looked like her, I pinned a tail on it.

Bad Example

A teacher says, “Okay, class. Today we're going to be talking about the tenses. If I say, I'm beautiful, which tense is it?”
Little Johnny raises his hand and says, “Obviously past tense, Miss.”

Yo Mama - Santa

Yo mama so ugly, she wore a paper sack when you went to see Santa so he wouldn't cry for the photo.