Hell at 16
I was able to grow and grow. Just eat and lift, you have enough anabolics flowing through your blood now anyway. The only way I would advise someone in high school to cycle is if you are going into your senior year and are borderline in getting that scholarship in football,wrestling, track, maybe even basketball(need weight for the post!)
In that case cycling something mild and gaining 10lbs of LBM, speed and alot of strength can make or break your future. College is expensive, and just because you go natural doesn't mean everybody else will. If you aren't even being considered for a scholarship save the gear for later on down the road.
Then again I have known average athletes to juice(weren't even borderline) and end up with scholarships. BUT and this is a BIG BUT, they busted their ass training for their sport to.
Juice is just a tool, it aint a miracle. If you do insist on doing it at least be educated to the potential side effects at your age, and accept them if they happen.
The last thing we need now is someone else that goes on dateline to talk about the bad shit juice did to them when they were warned from the get go!