What are some ways to impress a 15 year old girl?

I am 15 and i really like this girl? I have known her for 5 years. We are in the Marching Band together. I run cross country, play soccer, and I am a 2nd degree black belt in Tae Kwon Do. She is a very good Skier. But this year she cant ski because she tore her ACL. I would like to know some ways to get to know her better. Also I would like to know some ways to impress her and flirt with her. But at the same time just for now I don't want her to know that I am trying to flirt, impress, and get to know her better.