All you can do is love them and support them, the choice to work harder at anything must come from them. Some 15's will never need to be nudged and that doesn't mean they are better or worse than others. My oldest never needed nudging and a lot came easy to him. He has had some hurdles to overcome and he has given up a lot in the name of baseball but that is his choice. My middle one was the pudgy late bloomer who you wondered if he truly wanted to play. Now he has 3% body fat and is off to a top JUCO to play in the fall but that didn't kick in until he was 16. My baby is 16 and is just now working harder at it than in the past but he also carries all AP classes and his brothers didn't. I guess my point is if they want it, they will work at it to the best of their ability. And their personalities will guide them in how they get to where they want to be. 15 is a tough age, I teach freshmen every year and see all the turbulence they must get through each and every day. Just tell them daily that you love them and will help them with whatever they choose in life, baseball or anything else. Good luck to all of you, it isn't easy being a caring mom/dad! 