Run from her

This had gone too far, you have to get out, the door is only a few metres behind you. You can surely make it but you'll have to leave your your pants and trousers here. Running through the school half naked isn't exactly how you hoped this game would end, but the grounds should be almost abandoned by now, and anyone still here is probably inside. You could go out a window instead, which would give you a more direct route to the school gates but the drop from the second floor might hurt.