His threads are pinned because a moderator pinned them. He didnt pin them himself. As twin retro said if someone requests a thread to be stickied we will consider it and pin it if we think it's useful enough.
While I know you mean in case of someone confusing schooling establishment from shooting establishment (many of the same letters) I am still going to read that as lockdown (also known as lock in) for a pub
being drunk in school was either because drunk on playing field or could not be arsed with one particular Thursday afternoon so went and had some beers and played some games instead before returning for an ill advised last lesson/period