A boy comes in to school and starts throwing compasses at the teacher.
The teacher turns around and asks, "What are you doing?" The boy replies, “using weapons of math’s destruction"

Mathematicians are like Frenchmen: whatever you say to them, they translate it into their own language, and forthwith it means something entirely different.

What is the integral of "one over cabin" with respect to "cabin"?
Answer: Natural log cabin + c = houseboat.

A mathematician wandered home at 3 AM. His wife became very upset, telling him, "You're late! You said you'd be home by 11:45!" The mathematician replied, "I'm right on time. I said I'd be home by a quarter of twelve