last year my school almost exploded, though not from a bomb. a few days after 9/11, we all got evacuated from school around 6th period (that's about 11:30 or so). we not only walked the "fire drill" distance (out the door, you're "safe"), but we walked through the parking lot, up to the freshman campus building (about a 3 minute walk, without crowding).
needless to say, we were all confused. later that day, we got back inside, we hear from the principal, that the school's boilers got blocked up, and almost blew up. from what i heard, if the boilers, or even if just one, had blown up, the school would be a crater. from kids that were in the music suite (right over the boiler room) they said they heard lots of clanking and metallic noises.
i'd say an exploding boiler beats a bomb threat any day
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