How can get her to like me more than friend?

We met early in September and we turned into really really good friends and text/facebook a lot. Through all this I developed feelings for her and later I asked her out over the phone because it was the only way because she doesn't go to my school, hers is really close though and I had a feeling I may have had competition so I felt a little rushed. She called me back the next day saying she wanted to be friends. After like a week of barely talking we've gotten to go back to texting and chatting but as friends, in fact we're hanging out this weekend. The thing is I found out she likes this other guy but she said to one our mutual friends that she's only "involved" but things calmed down a bit since then (week ago). Now we're really good friends but I still have feelings for her. There;s got to be some way to sway her any advice?

P.S. I do want her to be happy, I'm just looking for a chance