"During such drills, they're typically told to leave backpacks and such behind."

Typically stupid.

Jackie, have you checked with your son's school to find out what the usual fire-drill-type procedures are? Also, exactly what plans they've made for a disaster? Living where you do, I'm sure they've got something in place.

There is a town in the expected lahar path of the local volcano here, and the school's plan is to immediately load up all the kids on the school buses and high-tail it out of the way. (Whether this will work or not seems rather iffy, as every parent within reach will probably be blocking the road trying to get to their kid, even though they know the plan.)

Sue