And if the "big kids" are sadistic bullies, what happens?
"big kids"
The teacher (or whatever you call her) is there for more than a salary. It seems that big kid bullies would be less likely to materialize, because they would have grown up in this environment as small kids who learned one way or another how to behave. But if the big kids were, in fact, bullies, then it seems likely (though I have no proof) that the teacher would then have to step in. The video I saw had a big kid - a girl - pulling another kid away who was hitting people. She pulled him away and sat him down and held on to him and controlled him until he got his act together. All I can say is that I thought this was great stuff.