All 50 U.S. states require schools to have a bullying prevention policy.

But a policy, alone, is not enough. Despite the requirement, there’s been a slight uptick in all forms of bullying during the last three years. Bullying can look like experienced basketball players systematically intimidating novice players off the court, kids repeatedly stigmatizing immigrant classmates for their cultural differences, or a middle-school girl suddenly being insulted and excluded by her group of friends.