I quit school when I was in the 10th grade, but I wouldn't have gone to my proms anyway. My school stunk and so did 95% of the students who went there.
When I was 18, my friend from a very small alternative private school asked me to go to his prom. He didn't want to go, but his parents were forcing him to. And rather than have to ask some girl he didn't like, he wanted me to go with him as a favor. So I agreed. It was one of those types of schools that no one listened to dress code even though the prom was supposed to be formal. A small handful showed up in formal wear. The rest would show up in assorted outfits and even jeans, a t-shirt, and Chuck Taylors. John and I were going to go in a rudeboy theme and buy matching sharkskin suits and take a checkered cab to the prom. However his parents intervened, insisted on a limo and him in a tux. He was NOT happy about it. I still wore a dark green sharkskin skirt and jacket with loafers. I was a chelsea girl at the time so I even had the haircut to go with it. It was actually a really cool prom. They hired the DJ of the alternative music radio station and he played a lot of ska (went with my outfit!) and goth (went with other people's outfits). There was another prom down the hall in a different ballroom and I peeked in on them: a large crowd of uncomfortably formally dressed Japanese kids from the prestigious private school dancing in a big circle to a rap song, "HEEEEY! HOOOO! HEEEEY! HOOOO!" putting their arms up and down. Our prom was waaaaay better.