Other children bully because they have emotional and developmental problems, or because they come from abusive families. They require our help more than our punishment.

The kind of bullying, though, that presents the most difficulty in figuring out how and when to intervene falls between these two extremes: Sometimes children who aren’t normally bullies get caught up in a larger culture of aggression  say, a clique of preadolescent girls who form a club with the specific function of being mean to other girls. Teachers must learn the difference between various sorts of aggressive behaviors, as well as the approaches that work best for each.

Most important, educators need to make a profound commitment to turn schools into genuine communities. Children need to know that adults consider kindness and collaboration to be every bit as important as algebra and reading. In groups and one-on-one sessions, students and teachers should be having conversations about relationships every day. And, as obvious as it might sound, teachers can’t just preach kindness; they need to actually be nice to one another and to their students.

Teachers also need to structure learning activities in which children are interdependent and can learn to view individual differences as unique sources of strength. It’s vital that every student, not just the few who sign up for special projects or afterschool activities, be involved in endeavors that draw them together.

Look at Norway, where the prevention of such incidents became a major emphasis of the school system after three teenage victims of bullying committed suicide in 1983. There, everyone gets involved  teachers, janitors and bus drivers are all trained to identify instances of bullying, and taught how to intervene. Teachers regularly talk to one another about how their students interact. Children in every grade participate in weekly classroom discussions about friendship and conflict. Parents are involved in the process from the beginning.

Norway’s efforts have been tremendously effective. The incidence of bullying fell by half during the two-year period in which the programs were introduced. Stealing and cheating also declined. And the rate of bullying remains low today. Clearly, when a school and a community adopt values that are rooted in treating others with dignity and respect, children’s behavior can change.

Indeed, our analysis of successful bullying-prevention programs across the United States and abroad reveals that the key common factor is their breadth: both in terms of the people who participate and of the deep connection between specific policies and the larger social ethos of the school community.

Involving the legal system makes a strong statement that a society won’t tolerate bullying. But for laws like the one in Massachusetts to succeed, they have to be matched by an educational system that teaches children not only what’s wrong, but how to do what’s right.