I agree that the main deterrent to bullying happens at home. I think the research is overwhelming that shows that children who are raised lovingly and responsibly are less likely to hurt other children.
But the schools also have a role to play. I suggest two things: First of all, teachers need to be out in the halls between classes with instructions to send immediately to the office any student seen pushing another, or calling out insults—any harassing behavior at all. Zero tolerance.
The other thing schools can do is work on developing a love of reading in children. There are many academic reasons to do this, but the social one is that books sensitize readers to other people’s experiences. Books have narrators to explain how a character is feeling, and what a character is thinking. Books can really bring us inside the lives of other people, in a much more powerful way than movies or TV can. It’s much harder to bully someone we feel empathy for.