I'd suggest banning 198.237.17.15*, but there's a bunch of IP vandals, so I second semi-protection.
I dunno about every school in the world, but except for one astronomy teacher I had (and me, a future educator), all schools and teachers I've ever heard of believe wikipedia is a little less reliable than Uncyclopedia.  I don't think the school is going to mind if we ban their IP address from editting.