Geek Humor

S. came home from school today and told us her beloved math teach had shared a joke in class that apparently had S. falling over laughing. Here's the joke:

Dear Algebra,
Stop asking us to find your X. We don't know where she is.We don't know Y, either. 

She laughed again (quite a bit) when showing us the joke. It's nice to know she has a sense of humor, even if it's a little geeky....