Giving him a bb gun would help him train in using guns for later in life, when he might want to start hunting. Contrary to what a majority of people think, giving a 16 year old a bb/pellet gun will not make him go crazy and just start shooting things at random. First of all, you should know as a parent if your kid can be trusted with a bb gun, and whether or not he will listen to you and not shoot animals or people. The pros of a bb gun would be that it would be a good training tool and it is a good way to get him/her out of the house. The only cons would be the area you live in. You can't really shoot one freely in a heavily populated area, the guns are way too powerful and shoot way too far. I would say to just ask your kid what he is going to do with it, where he is going to use it, and whether he is going to shoot with friends or not. See if you can trust your kid with a bb gun. Maybe before you buy your kid a bb/pellet gun, buy him an airsoft gun. They're less powerful and shoot 6mm plastic bb's. most of them don't hurt much when shot with, but see what he does with one of those, and that will determine whether he can be trusted with a pellet gun.