It became disruptive. Sexual harassment erodes the notion that school is a safe place to be. School safety is more than metal detectors and see-through backpacks and getting rid of lockers. Sexual harassment has to be seen within this context of school safety, because there are sexual assaults in schools. There are rapes.
Some kids are afraid to go to school because of sexual harassment.
Yes, even with little pranks. For boys, it's taken as locker-room behavior. There are parents who get absolutely outraged that a school administrator has dared to consider that what their child has done to be sexual harassment. Parents don't get to determine that. Not unless they put such policies into user-friendly words for the kids and really talk about what the policies mean.