this is great I say go for it. go around talking to people at scool saying what you want to do and ask for donations. I did this for my prom since we wanted to be the only two idiots to show up in a helicopter. We made 60 bones in two days. You have to be carefull though because the school is rarely down with solicitation.
also be carefull to make it subtle at the door when you get in since you can just get turned around. My friend went to prom with a blow up doll and just got kicked out. So make her slutty only when you are in. wow that last sentence sounded wierd