In my Advanced Functions class I've been teaching a unit on Probability, and I wanted to illustrate the difference between permutations and combinations. I set up four chairs at the front of the classroom and told my students I needed to form a four-person committee with a president, vice-president, secretary, and treasurer, and I was going to randomly pick four students to be on the committee.
So I looked at J, a black male student, and said, "Okay, J, you be the president," pointing him to the proper chair, and immediately one of my students said, "A black president? That's ridiculous."
I figure if the math gig doesn't work out, stand-up may be in that kid's future.
Image by jmtimages on Flickr.