Texas law allows licensed persons to carry at schools if the school gives them permission:
I imagine the school board/superintendent will be giving written permission to faculty and staff who meet the requirements laid down in their new policy.
I think it’s difficult for rational chaps like ourselves to understand school shooters.
But from what I gather they are usually bitter, resentful, desperate and ready to die just to make a ‘point’ to the World - which to them is actually just their School.
There isn’t anywhere else that many of them want to go to kill.
(Also, since the pupils are not allowed to carry guns, it’s an ‘advantage’ for the shooter over going anywhere else.)