I have a 13 year old also, I also have a son playing in college. I learned a lot the first time through and my 13 year old plays a lot less at that age than my older son. He takes breaks, plays other sports and I couldn't tell you what his average is. What I can tell you is I measure how hungry he is for the game. If he really wants it I will put the time and money into it. Ultimately it will boil down to whether mentally and physically they can handle the steps. If the game is no longer exciting and fun at 13 i would be take a break and see if he wants to play again down the road. But as a parent don't sweat it. It's a game that will end one day. Enjoy your son while he is young . He will go through slot of changes in the next few years. Enjoy the ride.