My kid asked me if he can stay out after curfew. I reminded him of the agreement we had with his probation officer. I told him, 'If you're going to play, you gotta pay. They called me from time to time with valuable information about his whereabouts and activities. Stop tolerating negative behavior.
Kids meet their bottom line when parents meet their bottom line.
Joining a self-help group such as ToughLove helps. The ToughLove organization helps parents find 'bottom-lines' and make changes immediately. At some point, there is a straw that breaks the camel's back. Parents need to decide what that point is ahead of time. Keep the adolescent busy with goals and structured activity.