teachers have changed, im not that old, (26) but i remember being in kindergarten and the principal being allowed to throw down the occasional yard-stick to the behind, wasn't a federal case.
i remember i was a counselor at a camp for troubled kids, and one kid didn't bring his medication for the week. he was constantly on the verge of losing it. one day he was running his mouth and i handed him the broom to clean the bathroom, he lost it and attacked me with the broom. i was 17 and he was 8, and im not a big guy. i got hit by the broom a bunch leaving some nasty knots on my head and welts on my arms, but i managed to get him in a head lock and pin him to the ground until he decided to calm down, which was like 7 or 8 minutes in full view of other counselors.
needless to say, i wish somebody had had a pair of handcuffs.
every situation is different, i would think that school security [do they still have security guards at school? they actively broke up fights in my middle school] would be enough to subdue and reasonably restrain a kid who is freaking out like that, i dont think you need actual outside police to help out.