Let them graduate to nothing for the disruption they have caused and interruption to study of other students. Gaol should be a good place for the ringleaders. The only problem is that the fighters are not at the top of the academic cake. They fight rather than study.
The values of education achievement are being turned upside down. The real men among the students are at the bottom of the academic scale for the school. The high academic achievers are the school nerds who hide when the fighting is on.