When McGonagall was young she went to Hogwarts. She was in Gryffindor, a house for brave and bold students. When she got older she decided to train herself to be an "animagus", a wizard who can change themselves into an animal without a wand. She can change into a cat. Later, she became a member of the Order Of the Phoenix, an organization trained to fight evil wizards. In a quidditch match, she was hurt by a Slytherin player.