You don't

You expect Longwood to frown. Instead his smile gets even wider.

"Well when we have students who don't want to earn points those students usually don't go very far," he tells you. "Go back to your room and have a good think about what you want to get out of your time here."

His words compel you to leave, so you start walking out of the hall to obey him. The second you walk through the door, a breeze hits you, throwing your cloak up and revealing yourself to the whole room. You control your cloak and see Longwood holding his wand.

Everyone else in the room is looking at you.