How do I get people to think differently about me?

Okay, so at the beginning of my junior year, I was, well, not the friendliest kid in the world. Well, for one thing, I was known in my Algebra 2 class for a throwing a hissy fit after being kicked out of the classroom for sleeping. (No screaming or anything, just being pissed off and shoving people out of my way to get to my desk for my books after the period ended) (Im a guy, by the way, ur average, tall, lanky guy). I also have a made a few people dislike me, a high school athlete and this one kid who I don't really care about because he is so annoying and fake that it disgusts me and this one homosexual kid, (I didn't have him hate me because I knew he was gay, Im cool with his sexuality, but we just had a fight and I never talked to him again). Anyways, things like that happened, and i would have this aloof personality as well. Now the year is almost over, and senior year begins in 2011-2012. I was wondering how I can get my people to think differently about me. It's getting lonely without talking to people, and I dont know who in my school does not care for me or doesn't really know about me (Im only talking bout the high-school athletes and cheerleaders, like several of them in my English class who I bet that THEY think I am not at all much friendly.) Is it too late now since it's been a whole year of this, or do i still have a chance? What do i do? How do I do it? (NOTE: My aim is being friends with the high-school athletes and cheerleaders)