Umm i have a problem. I really want a girlfriend but i've only had one poor relationship. help?(girls)?

I get along with everybody at school, generally everybody likes me. I'd say i'm a really nice guy, complimentive and supportive, and judging from other people's responses to me i'm pretty funny. I have a lot of chick friends, i get along with them pretty well... but i can't get a girlfriend. I'm also way above average fitness level too.. the girl i like is in my gym cl, and in the fitness contests im always about 5th-10th out of 100 people. I also have the best amount of crunches per-minute in my grade (freshman) and i'm one of the best bikers in the state, judging from the several state competitions i've done. I do get rather bad grades but im in honors cles and i'm pretty intelligent. Why aren't girls attracted to me? i'm about as dark as it's possible to be while still being Caucasian, and i have black curly hair with about 1 inch diameter curls. I have good hygeine, i shower at least once a day, brush my teeth twice a day, use deodorant and i use mouthwash too.