the way around it is to simply go to
www.anonymizer.com BEFORE you go look at anything else on the web. By going through the anonymizer site all your school or history folder will detect is "X" amount of time spent at the anonymizer web site. If the school blocks access to that site then you just have to get to an off campus machine and download the Anonymizer browser plug-in. That nifty little jobber just prevents your cookies,history or any other loging system from registering anything.