our school makes us huddle in a corner during a lock down drills
right next to the door.
if something real ever happens(Like a gunshot is heard), I will say, "forget this system, our lives are in danger!"
and barricade the door and windows.
If the teacher is enough of a dumbstuff, she or he will threaten me with some punishment, I would just tell him or her, "forget your punishments, I like my life," as I barricade the entrances.