Personally I would say overreactive, school protection areas are usually pretty good.
But I'm old the one year( like maybe 5th grade?) Went to school blizzard picked up the school was going to have us stay overnight in the gym, about 430-5 storm broke and they sent us all home on the busses. LOL.
Really do whatever makes you feel best.
My belief is that you have to be underground to get to that 90% survival rate in a mid range EF4-E5. Most schools don’t have the ability to make that happen.

