You took the bait, Stupid. Think again. The rest of the school gets to live.
If all teachers had the ability to control all the partitions, the numbers of dead would obviously be lowered when the first teacher that activates their neck-card (in seconds) can touch-button the partitions that need to be activated. The shooter is captured. The rest of the school has the right to safety from the shooter, just as would hostages captured in the apparatus along with the shooter.
Stairwell partitions could close off entire floors instanly, such as the example teacher featured in this thread. The drill would teach that, if the shooter is on their floor, a safety apparatus inside the classroom shields/locks the door and another is unfolded so that the students can hide within it, made of kevlar, etc. if the shooter decides to shoot through the walls. Other distractions to the shooter so captured might include activating only certain parts of the sprinkler system.