Excellent idea
despoticruin
If you are using household concentrations you won't generate enough chlorine gas to be harmful in a ventilated area, like outside. If you put it in a bag and huff it you are going to have a bad time, but enough to cause damage can be tossed into a mason jar, shaken, and thrown pretty safely.
The acid makes it rust in seconds instead of days though, instantly visible and quite permanent damage.
Well, a 1:1 mixture of chlorine bleach and vinegar should damn near instantly and permanently corrode the steel. Don't breathe the fumes, but I have toyed with the idea of a squirt gun filled with instarust.
It depends on the school, but here in the US it is generally expected that the majority of students return home for the summer. Most universities have housing available over the summer but it is limited and generally reserved for those with disabilities and graduate students who are expected to attend the school for 4+ years. Most college students only go for a year or two.
The silicon die could easily chip a tooth as well, the stuff is insanely hard.
While this could work, please don't go firing a laser powerful enough to set shit on fire randomly into the air. It's like firing a gun, that laser will fuck up whatever it hits and you don't know what's behind that flag. Easy way to kill a plane full of people by instantly and permanently blinding both pilots. I would look into artillery calculations and water balloons filled with bleach. Pretty easy to hit a stationary target with a pi handling trajectory calculations. Paintballs might be another option, bright pink.
I highly recommend Schachnovelle by Stefan Zweig