[bitesize]

I'm guessing you're a guy?¿ If I'm right, don't worry...most teenage guys are exactly the same (and teenage girls for that matter...puberty is a cruel, cruel time. ) Liek Emily said, a lot of us tend to be initially attracted to people by their looks which is totally understandable. i wouldn't worry about it, it doesn't mean you're especially shallow, or 'addicted' to pretty girls.
I can't really think of any tips to become less shallow...hopefulyl withoiut sounding patronising, you'll probably find things will get a little different as you get older...they did for me and a lot of other people I know, anyway. Often spending time with someone who you wouldn't initially consider very attractive and getting to know them can make them seem more attractive and soon you'd forget you ever found them unnattractive in the first place...