A long overdue change in the law. Touching another person without their consent is assault, and the defenses for that should be limited to genuine justifications: "self defense against an aggressor" is one, another would be "he was unconscious in the pool and I pulled him out to save him from drowning, it wasn't possible to ask if it's okay to touch him first".
But "I didn't approve of their behaviour" is not a legitimate defense against an assault or battery charge, there is no reason this should be different just because the person you assaulted is a minor, or you are their care-giver - if anything, both those things should be AGGRAVATING circumstances, not defenses !

All other considerations aside- you can't teach discipline. What passes for that is merely teaching fear of reprisal, which is useless as it only extends as far as the RISK of reprisal. Discipline is a useless thing to teach.

Self-discipline on the other hand. Now THAT's worth teaching.