But it looked like she had already fully escalated and the students were unsafe. I support him going in there boldly - it at least focuses her attention on the immediate threat instead of the students.
We are trained in Non-Violent Crisis Intervention, and have to be re-certified every 2 years. Under no circumstances would we approach an out-of-control individual face on with a finger pointed in their face. Safety is always number one.
First, report and request assistance (if poss), assess and clear area, approach calmly side-on (never face-on.. more area for assailant to hit), low calm voice, de-escalate.
You have to think super-fast, and that's where the constant training comes in so you do it second nature.
I haven't had to deal with anything this extreme in my current position (altho my Vice-Principals have, hence the school lock-downs)... but I could tell you some pretty hairy stories Mark, believe me.
Of course the VAST majority of students are great..but unfortunately it is part of our job to be trained in dealing with crisis intervention.