most school systems these days would be happy to take a few extra bucks.
One would think so, but a friend of mine almost got fired for selling off unused (sat in storage for 4 years) equipment from the theatre. It's not like he took the money for himself; the administration found out when the check arrived, yet they still considered it "theft" of district property. Words cannot express my disdain for this policy, as the equipment in question would have sat in storage for another 30 years, until being thrown out (literally, in the dumpster, regardless of operating condition) during the next remodel.
I'm not suggesting that people shouldn't try elesewhere, but make sure what you're doing is within the rules or else you could be putting someone's job on the line.