I've been there plenty of times before.. Ok, so what I would do is just try to start a conversation about something you can both relate to. Then ask him if he's planning on going. If he says yes, ask him if he would like to go with you. If he says no, still ask. Either way, if you don't ask, you'll never know. It's too good of an opportunity to miss.

Ask him if he's going to the dance