Im 15 years old...i will be 16 in one month..i was wondering is it true that weights stun your height?and how heavy weights should i lift at this age?

I did weight training from the age of (about) 16 to (about) 21. I grew from 5'10" to 6'2" in that time.

Mind you, I also played rugby and squash, and ran 4-6 miles most days.

I'm not sure that all the exercise (and the consequential huge appetite) was necessarily a cause of my late growth spurt, but it sure as hell didn't stunt my growth.