School Computer Software?

ok, i know most people will say "why do you care" but i plan on pulling off a prank pretty soon and i know very little about school security software.. i'm pretty smart with computers (i've changed the admins pword and didn't get caught..) and i was wondering if you could tell me what computer software my school has, i understand if i don't have enough info.. but please say that, just the name of the software would be nice. ok, so this is what i know our school can do, when you log onto the schools network with your account, our admin can go to the computer that you just used and tell who logged onto that computer.. also, when you are on the internet, our school has a filter that tells the admin what sites a certian computer was at at a certian time, so if lets say im on computer 23 and look at a site, they can tell that it was computer 23 at such and such time, which then can see i logged onto that computer at that time... what my question is basically, is what software could they possible be using (our school is super small and doesn't have alot of money...) and if i used a proxy, then could they possibly see what i looked at (IM NOT LOOKING AT BAD SITES im just curious, i personally would like to surf anonomously (sorry for my bad spelling) thx alot, hope this isn't to long