Quite a few people do wear them but I personally don't like them, I'd rather have a nice diamanté clip rather than something like a tiara, in the uk prom king and queen isn't like in the us where it's a big deal in fact at my school I don't think we do prom king/queen.
Since a tiara represents queen/princess, yes it's weird to me at least. But I graduated in 2007, you may get grief for that opinion if things have changed.
