A teacher is going over the rules and exceptions for missing a test for class.

"You may only miss a test in the class if you have a doctors note, a family emergency, or if you have a other immediate emergency."

One of the students asks, "What if we are too tired from, well...'sexual exhaustion' ?"

The teacher smiles for a second and says, "Well, I guess your going to have to write with your other hand."