I had some experience with Violent girls when I was younger, i went to school until 2010 to get a time frame. Even when then it was already pretty common for them to first beat their victim and then run to whatever teacher was around and get them to punish the victim as well, as they had "provoked" the violence, this was especially true if the victim was a boy.
I've also seen female teachers actively supporting mobbing in classes, in one case one of the teachers left the room to avoid "seeing" the mobbing and be responsible for it.
In any case, at the same time most Male teachers, seem to be unable to act in any way against such behaviors, my guess is they try to avoid repercussions which would hit them harder but it's not so far off to imagine a lot of them are willing to accept this female behavior as most male feminist would, unable to see any behavior on the part of women and girls as problematic.
On the bright side, I have also seen great female teachers who were able to recognize the behavior of these students and acting accordingly to help victims of such an abuse, which was good to see even though they most likely do not have to fear the same treatment as a male would.
It's flabbergasting actually, my school years were not that long ago and I made friends with a lot of those who were bullied, I never liked such behavior, but for some reasons those, men now, are some of the most adherent feminists out there, some of them I lost as friends on the way because of my MRA activity.
In any case, that women and girls can be and are Violent is something everyone *does* know, I'm sure of it. When talking to older people especially, those who are living with a spouse for a long time, it always seemed to be common knowledge that women can be just as Vile as any men can be and everyone knows examples of exactly that happening.
So it's just puzzling to me how we can all pretend that this is some extremely uncommon occurrence or that women are always also victims when they are perpetrators.
It's just the Emperor's new clothes to the extreme.