She was prim and proper, educated, and wielded en enchanted umbrella. Was Mary Poppins trained in the magic arts at Hogwarts School of Witchcraft and Wizardry? It makes so much sense! The various clues for this fan theory are explained in a video from Uproxx. Don't let the fact that Mary Poppins was a Disney movie and the Harry Potter films were from Warner Bros. make you doubt it. Remember, they were all together in the library to begin with.