"Someone might misuse it" isn't a good reason to deny a constitutional right.
Arguments similar to yours could be made for lots of places people might misbehave. Let me think of some...
- Polling place
Court/Court office
Racetrack
Within 1,000 feet of execution of death sentence
Business that makes at least 51% of revenue from on-premise alcohol consumption sales
Sporting event
Hospital
Amusement park
Church
Meeting of a governmental entity if the meeting is an open meeting
Your reasoning is why I, as a non-drinker, have to look for 51% signs. Carrying under the influence is already illegal. So is being negligent with a firearm, in or out of a school.
And despite your examples, LTC holders are 21 times less likely to commit a crime than the general public.
Twenty-one times.
It seems crazy to me that I can carry at a park, a mall, or any number of other places where kids roam free but NOT in the school where my wife teaches or the schools that my kids attend just because someone else might be irresponsible.
(And although I'm currently in an armchair, I'll add that I've worked in higher ed & K12 and that I have at least a dozen teachers and librarians in my extended family... including my parents and MIL.)