Hey man, I'm a sophmore male in Charlotte. We really don't have that many dances until our Junior and Senior years. I have been to other dances, but I'm not one of those "cool" kids who can get a date easily, so I can't realy say much about that
Anyway, here are a couple suggestions that I have noticed:
Everyone knows your a freshman, but they wont care as long as you don't try to be something you are not. Just realize that you are low in the food chain and insulting uperclassmen or trying to be one can lead to trouble. I'm not trying to scare you or say that you can't be friends with uperclassmen, just don't try to be one or claim that you are better.
As I said before, dating is'nt realy my strong point, so I realy can not help you there.
Try to be diverse with friends. It is fine to have friends from multiple groups and be flexible. I like sports(even though I realy can't play them well) so I'll hang out with a group that likes sports (LIKES SPORTS-NOT PLAYS) and hang with them, other times I'll hang out with a more geeky/ gamer group because my true passion is video games, and other times I'll hang out with the group in my neigborhood because they are close by, we like video games and share an intrest in punk and classic rock. Diverse friends are helpful because I have had experiences where friends will realy just stab you in the back to be popular. Diverse friends always gives you options if you are suddenly hated by a group or you suddenly hate a group.
Sorry that these are kind of broad tips for highschool altogether, but I really don't have much experience with dating or dances, but I tried to help as much as possible.
Hope all goes well.