K.O.
He's 15 & bored! Get him involved in something that he has to get up early every morning, especially on weekends. Either a job that he has to do some sort of education while he is there or a volunteer work that he has to learn how to care for someone else. Maybe if he sees what it takes to make money, he may well try a little harder in school. Either way, he needs to understand that if he does not stay in school, he will have to go out & get a job; any job. If you have a friend that has a restruant or a cleaning service; ask them to give him a job on the lowest rung & teach him what it is like to work without an education. That will wake him up if nothing else will. Good luck.