XD might have a point.
The badge weighs heavy on some LEOs, but much heavier on some of the guys who work as security guards because the police wouldn't take them.
If he works for the school, give him a couple weeks without pay to think about the disadvantages of enforcing rules that don't exist.
If he works for a private contractor, have them reassign him to other work outside the school system.
Either way, his coworkers should get the message that too much zeal can be a bad thing.