Mildred Hubble's first term at Miss Cackle's Academy for Witches starts badly when, unlike her classmates, she can't control her broom, her kitten, or her spells.

Disaster-prone Mildred Hubble finds that despite her best efforts she still manages to get into trouble at Miss Cackle's Academy for Witches, especially after she is put in charge of the new girl, the seemingly placid Enid Nightshade.

Resolving to stay out of trouble when she is assigned the important task of lighting lanterns and candelabras every evening, Mildred Hubble finds her efforts challenged by the arrival of an exuberant stray puppy who loves to fly on broomsticks.