Some of this has probably already been said but i could only be bothered reading the first 2 pages.
To get cmd open a wordpad and type cmd.exe and save it a <filename>.bat try not calling it cmd as it is blocked in my school so i called it blah and it worked fine.
You can try downloading 7-Zip as it for some reason allows you to see all the directories in the network even the hidden 1's such as the c: drive.
You can open internet options in IE, if this is blocked create a shortcut to "control" this will bring up the control panel and access internet options from there then under temp internet files click settings then view files from hear you can list down the directories untill u get to the c: drive. ( this works in my work but not at school but try it at ur network anyway)
also if there is anyweb blocks try and enter the Ip address of the site instead this work for a while untill the admin caught on a blocked all IP's. To get the ip adress in the command prompt enter ping www.blockedsite.com and it will show you the Ip
This is a bit risky and is a very easy way to get caught but it works. If ur teaher has admin status which mine does coz hes the head of the computing department when he leaves the class run net cat on his box and telnet to it and ran the batch script someone posted easiler to add an admin account or since u have access to the box just run the script on his computer
