My old school had 2000 highschool kids and only ~90 went to the prom, some said it wasn't worth it; but I mean, every school is different. My current school has around 120 people per class so that's pretty small, the prom would probably have a lot less than 90 but we'll see.
I never went to any prom or dance, and I'm a Junior. I don't really like going to school dances/proms, especially for how much is costs, you don't know if it will be worth it.