He of course will need a dance belt, which is a sort of "jock strap" for dancers. Hopefully there will be a male salesman at the palce because it might be a bit embarassing for a 13-year old to discuss how to wear one with a female.
As for tights, black ones will do fine. For the top, a white T-shirt will do fine as well. A unitard (or "biketard") will do nicely as well, unless the school has a specific uniform that they require, which I think they would have told you about and where to get it if they did.
Brian Christiansen[/i]