You shouldn't have any problems playing the game, as it uses the standard protocols. Updating however, uses a P2P system which a lot of schools ban or throttle.
*EDIT* Bsphil has the best short term solution for you, assuming the connection you jack into is quick. If it's not, well you're screwed to only getting major updates at home or via a friends ISP. Since we're on the subject, I'm really dissapointed that none of the recent "major" interviews with Yoshi even asked about the tobic of downloads. Surely, ZAM at the very least, sites have had tons of threads about the updater...
Edited, Oct 20th 2011 10:07pm by Perrin
FFXI:Sylph - Perrin 75 Hume THF; Retired (At least from my use any way)
EVE Online:ScraperX; Retired
WAR:IronClaw- Peryn SW;SkullThrone- Grymloc BO; Retired