re: Fellow coach lost his mind at practice yesterday. What would you do?

Yeah, that'd almost certainly be a firing offense dealing with Pro or college players, doing it to an 8th grader is child abuse, I had coaches yell at me or grab a facemask, but full on tackling a kid (and it is a kid in 8th grade) not a slow tackle to demonstrate technique but an actual tackle-- that's a no second chances type of thing and possibly a call the cops thing.

Actually depending on what state you're in, you may need to call the cops-- as a youth sports coach I think you're a mandatory reporter and if the kids parents get involved (and frankly they should) you need to have reported to protect yourself.