Is it illegal for headteachers in the uk to look at students FB acounts?

[Red]

He didn't "hack" into it, you left it logged in.

And no, it's not illegal; if you didn't want that information available to people at the school, you probably shouldn't have gotten on there at school.


EDIT: So you're telling me that Facebook, one of the largest tech companies in the world, one of the most invested in internet security, with a department comprised of hundreds of people whose sole job it is to prevent people from hacking the website, was hacked by a school teacher in Europe?

Again. You left it logged in. You friended him. You didn't have everything set to the correct privacy settings. No one "hacked" you.