i am 15 and dont think there is any set weight to weigh!you may have heavy/light bones and at the age of 15 everyone varies because of puberty!as long as you do regular excercise and eat healthy!
look in your favourite celebrity magazine. OR, option 2, develop a sense of worth in yourself, and not one handed to you by the latest token fool in the media spotlight who has ben digitally touched up and actually looks like a dogs ass in real life.