For 'The Prisoner of Azkaban (2004), Alfonso Cuarón asked the kids playing the Hogwarts students to wear their uniforms as they would if their parents weren't around

This is in sharp contrast to the first two films; where they wore their uniforms in a very orderly fashion. pic.twitter.com/2mAOqrvr9w

— Harry Potter Facts (@Muggle_Facts) June 30, 2020