Sadly dresses really aren't equivalent to suits. A guy can wear the same suit multiple times and not cause any comment, but a woman will get one is she wears the same dress especially to dances.

There's a status thing and culture thing going on in high school around being able to wear different dresses to dances. They can be found quite cheaply, but picking out a dress for each dance is a part of going to the dances.

Its annoying and it'd be nice if we could get away with wearing the same dress over again, but in high school, its tricky.