Yet here's another example of how students these days think they are/are allowed to get away with just about anything. I wouldn't be surprised if she (the student) probably has a history of bad behaviour and getting into fights (what she calls "arguments") on a regular basis. Probably disrepctful to her teachers as well. If that's the case, then she deserved to get roughed up a bit. Don't dish it out if you can't take it.
If the student, however, is one of the school's "model" (i.e. one of the school "nerds"/academically inclined) students, or is just one of those students who are really quiet, stick pretty much to themselves and who don't make a lot of commotion, THEN charges would be warranted.