How do i get close to this girl that i really like?

[Krste T]

okay i am a junior in high school and i am really starting to like this girl on the tennis team... And since my friend and i are both tennis players we always go to watch their games and sometimes hit around with them. The girl i like is always laughing and is friendly so she has a great personality but she has a small group of friends so i cant really start hanging out with her. Sometimes i see her in school and ask her how her game went and it usually goes pretty well. Today i watched her game and talked to her for about 10minutes after. Conversation went great and when we were leaving i was going to drive my friend home so i offered her and her friend a ride but she said no thanks i dont want to make it drive around dropping all of us off ill just call my parents. Since she doesnt have a facebook or i just cant find her on it... How do i really start talking to her? Oh and i dont want to be stuck in the friend zone again so i really want to make a mive