That's an extremely unacceptable mistake. We can't have senile people teaching and protecting our kids. Would you want Trump or Biden as a history teacher?
Not that dumb of a mistake. For one, why would a teacher have their gun out when there isn't a shooter? It should pretty much be locked down at all times. School shootings are rare believe it or not.
That could be true though impossible to know. More importantly is the count of lives lost. If you can stop a shooter before they kill the next ten kids, how much of that compares to the likelihood of mistakes? Also consider the likelihood of the teachers being armed simply deterring potential shooters. We've already established that most of them are planning to die in their shootings anyhow, but it's still a factor.
Bravery maybe but not training. More guns than hands is lunacy. Also the guns should be locked up. Don't put your dumb mental image out there like that's what I'm suggesting just so you have something stupid to argue against.