Can my school punish me for something i did on fb that does not involve them?

[Michael T]

things that bring bad feelings or bad publicity to such an institution do effect them.

they should boot your Butt out of their school

as to the police you had to access her facebook account from a computer connected to the Internet

there is a record of that transaction [computer at ip address logging on to that FB account at such a time and posting this information] which the police can retrieve and use to nail your butt to the train tracks

to the rest of the internet world reading this

relationships are seldom permanent and the acquaintances you make for the most part are not trustworthy
use your password to protect your information
sharing your password is stupid

it allows the other person to use your account for nefarious purposes

Don't be Stupid keep your password to yourself