Like this girl but I don't know how to tell her. Cause she's 17 and I'm 15. How do I tell her. A note or just be stright up onest :confused:

You don't "tell her." You don't write in a note "do you like me, check yes or no."

Start talking to her... read her, and then if you see some interest being returned ask her if she would like to meet you for dinner/movie.

Don't ask "You wanna go out?" but rather say "Im going to do this... wanna come?" that implies that you don't need her, your not trying to impress her... but rather she is an addition to your already great night.