I'd read up mainly on active directory and group policies, basically unless the school is full of angels you'll need to lock everything down giving them the bare minimum of functionality. The problem then comes with exam boards, some say they must have right click etc.
The other things you'll probally want are a corporate antivirus solution managed from a server, that makes managing exceptions and virus alerts so much easier than stand alone clients.
Netsupport school is a good one too, remote control any pcs you put the client on, remote power on etc, execute files at client (brilliant for mass installs) and watching suspicious behaviour/gathering evidence. Just don't put it on your servers (especially when you can use terminal services) or any staff machines incase the kids work out what they're up against and put the demo on pendrives

Poorly implemented its a massive security risk, done properly its an invaluable tool, all it takes is changing the ports from default and suddenly downloaded versions can't see your clients.
Web blocking's probally the other main thing, we use Policy Central Enterprise (the councils banning is useless to say the least), it sits in the background monitoring everything, each time a flagged word appears anywhere on the screen it takes a screenshot and dumps it on the server which you can then view from the web-interface, it also logs all internet activity and allows you to globally ban sites in a few clicks, its got the Bebo'rs running scared, they can't fathom whats going on every proxy they find find is blocked in minutes. For repeat offenders it can disable their net access and their internet explorer for pre-defined ban periods, it's a very powerfull tool.
Capitas SIMS program might also be worth a look, but that'd depend on whether you're LEA uses it. Powerout maybe too, turns you're machines off at a preset time so you don't have to think about it at the end of the day, you could get a site license for £99, you'll save that a term in leccy bills.
You'll probally be asked to look after everything technical in the school from remote control batteries to data projecters to security cameras because "you're IT" and you'll find some of the main problems come from technophobe teachers.
But above all be prepared to walk into a disaster zone, chances are it'll be a mish mash of systems made worse by laziness/incompetance/lack of investment. You'll also probally be the most hated person in the school for blocking internet sites
