Sorry but a lot of anger here... calling all teachers, lunchtime supervisors, parents whose children have experienced bullies/aggression in the playground...
if a child is not having fun at breaks/playtime, due to children who "don't know any better" (so it seems to be an excuse for letting them continue with their bad behaviour), has a school/school employee ever been able to make things better or does it just get worse once parents start to complain?