I'd suggest eating a few hard boiled eggs instead. I would think getting him in the habits of getting his nutrients from whole food would benefit him in the long run.

It's slightly more than $7.00 per day for the minimum recommended dose. Optimum Nutrition BCAA is $0.20 per recommended dose.

I don't know if it safe or not for someone his age. If it is indeed safe, it would be really hard to convince me that their proprietary blend (at least a yellow flag for supplements) is worth $7.00 per day.

Regardless, real, healthy food and lots of it will go much further in the weight room. Take advantage of the natural teenage metabolism and growth while it's there.

At that age creatine and maybe a protein supplement like ON whey is the only thing I would use. You get plenty of BCAAs from normal foods and in a year or two his hormones will almost be at steroid level