How to make a admin account at school

First get on command Start>Run>type CMD then type in net user /add pwnedschool or w/e you want the name to be. then you can sign off and log onto the name you made and BOOM there u are admin. And if you can't get on command Open up IE or firefox w/e your school computer uses then go to View Sorce then click Ctrl-A and dele all the stuff and type in
@echo off
cmd
then save the file as a .bat so u can save it like admin.bat or anything like that. hope it works for you need any help just ask me.