When I was in school it was unthinkable that a student would actually attack a teacher.
It's often the parents who now come in an assault the teacher so why wouldn't the students think it's fine to do it as well? Now as well so many children see adults bullying online, making disparaging comments etc they think it's fine to do that as well. After the recent Olympic road race a British rider who really did try his best, it was obvious but didn't win had mostly good messages sent to him but some were just plain nasty for no reason at all. We had a female here threatened with being raped and murdered because she suggested Florence Nightingale be put on our new five pound notes after the Bank of England had asked for suggestions! A friend of mine attracted the same type of attention after an MMA fight, she had comments from around the world aimed at her. She's tough, articulate and very intelligent but those messages knocked her for six, the sheer nastiness aimed at her by so people she didn't know and never would. How must children feel when the same happens to them, when there's an insidious campaign against them?
Adults must take the lead here and teach children it's not right to bully, we must also make sure it's not the adults who are doing the bullying and if you look to public life, the politicians, the so called divas of the entertainment world, the media etc they need to understand bullying is wrong as well. Then perhaps the children will learn that bullying is wrong and the consequences will be nothing they like.