I need some help on "cracking" a PC @ school

here is what is the deal:
My PC science teacher said that if I can break thru the security of the PC he will give me a 10, so here is what I need to do:
1. Open GPEDIT.msc ( to disable the restrictions)
2. Open C:\ and enter in the Windows directory and the final step (and the hardest I think) to change the Acount tipe from limited to administrator.
And here are the problem in doing those steps:
1. I have a limited acount
2. The CD-RM is not visible in explorer nither is C:\ or D:\
3. gpedit.msc, Cmd.exe, msconfig, run, right-clik saving files from the internet, and opening rar,exe,bat.... files are alos restricted
I could enter in the BIOS of the PC but that I thin dosn't help, so could anybody help me in this?

Thanks

CRISTI