We were told if our hiding place was compromised prepare to fight until the shooter is incapacitated. Throwing things distracts the shooter. Pounding a fire extinguisher into his skull incapacitates him. Whatever you do, commit 100% to your plan.
I teach, our training was school shooter based, running was recommended for younger kids.
As a former baseball coach I've always had at least 1 bat in my room that I would use in a worse case scenario.
I'd rather be armed and have others in the building armed, but I think that in the stressful confusion of an intruder shooting situation I'd want those armed to have some training beyond ccw training.