Nothing seems to work, what can I do to change myself?

I'm 14, honors student, straight a's, but when it come to girls, I am an F. Here's my situation. I have asked out 17 girls (over the course of 3-4 years) and I have been rejected 17 times. Yes, I know, I am a loser. So, I know it has to be something wrong with me. I really don't think I am ugly, I am not arrogant, just confident. Is it because I'm not a jock (I do like to watch sports though, big fan of baseball) and I'm not popular? I don't what to do, except come here for help. What can I do to change so this streak snaps? Thanks guys.