Orion's slip says Room 30. After he's performed some perfunctory ablutions and walked Chloe to her homeroom since they're on the same hall to begin with he finds his, though it requires a fair amount of map-staring. He goes in - it's a little room, only fifteen desks, two people here before him but they're doing really thorough checking of the place. Seems like overkill, anything really bad would be easy to see in a little room like this. Unless the one of the desks is a mimic? He kicks the desks. None of them are mimics. He sits down in the last one he kicked.