S24E15 Black-Eyed, Please
Lisa cannot understand why the extremely well-qualified substitute teacher Ms. Cantwell hates her so much and cannot reason with her. Meanwhile Ned punches Homer and feels very bad about it. However Homer comes up with a way to atone for it. Through Edna's intervention Bart is set upon Cantwell and she is soon clearing her desk - as well as telling Lisa the reason for her hatred of her.