3. We've lost the village.
It used to be that bus drivers, teachers, shopkeepers and other parents had carte blanche to correct an unruly child. They would act as the mum and dad's eyes and ears when their children were out of sight, and everyone worked towards the same shared interest: raising proper boys and girls. This village was one of support. Now, when someone who is not the child's parent dares to correct him, the mum and dad get upset. They want their child to appear perfect, and so they often don't accept teachers' and others' reports that he is not. They'll storm in and have a go at a teacher rather than discipline their child for acting out in class. They feel the need to project a perfect picture to the world and unfortunately, their insecurity is reinforced because many parents do judge one another.
The rule should be: once the bell rings, the teacher is the boss, the kid must do what the teacher tells them, even if it's stupid.
Now I realize that some people would be aghast at the notion of not questioning authority.
There's a time and a place to learn to question authority. It's not in elementary school.
Of course there should be exceptions for dangerous, criminal or immoral behaviour.
But 99.99% of what of teacher requests do not fall in those categories.
If the teacher has a problem, the parent should talk to the teacher. Not the kid.
A teacher cannot maintain discipline if she thinks she will not be backed up by the parents. Even if the teacher is a complete moron, it's important for the parents to back her up, because if the kid learns he can divide and conquer, his next teacher will deal with the consequences of that.
The same applies for other adults: neighbours, store owners, camp monitors, etc.
We need to reinforce the idea of adult solidarity. If the responsible adult makes a reasonable request, and if the kid doesn't comply, the kid is at fault, not the adult for telling him to comply.