Well...Coming from a 32 year old man who has...been around the block you could say.
1) when the ask her if she wants to get something to eat after school, tell her that you like her...make sure you pay. be funny listen, and don't try to get into the pants right away. be her friend.
2) if it all goes south and her friends tease you and she lets them tease you then you need to keep on going, nothing worse than a person who cant stand up for themselves of what they like. if that happens then she is way to immature to want to deal with.
3) find some one else who is actually real to you and your friends, that will solve it's self out. good luck