I was in france for my year 10 formal, so i missed it.
I took a girl from out of school in year 11 and it was the ghey. I mean, she was a year older than us all and quite teh sexy thus quite a good dime piece to show off, but it meant I had to chill and make polite conversation with her all night instead of be my normal raucous self.
Fortunately two of my mates brought out of school girls and found themselves in the same predicament (just their dates were younger, thus received less respect).
In year 12 I asked one of the best looking girls in the grade to come with me on the day of the formal as she wasn't taken just so I could have someone hot to walk in with, I didn't particularly find her personality attractive at all. We didn't sit together which was good because 1. I didn't want to sit with her and 2. Me and most of my friends went to the local pub as soon as he meal had finished and we had had a bit of a dance as the Australia Uruguay soccer match was on.
Basically I am trying to point out that taking someone to the formal is a redundant exercise, and while you may seem "cool" or whatever, it usually turns out to make your night worse. Just ask the most attractive girl who doesn't have a date to go with you an hour before hand so you can be in photos as a couple when you walk in.
