Don't fuck with school computers, it's not your property. If you wanna mess around with Linux, I will literally send you my laptop. Don't get in trouble when it's not necessary, especially because it seems like your reasoning for this whole thing is, "they left a door open", like my cat every time I open the refrigerator. And just like my cat, you will be tossed out.
Looks like it's too late to sign up, I just tried and it kept telling me to "verify that [I'm] not a robot" without giving me anything (like a captcha) to do so.
Shove it up your butt