My 14-year-old daughter, Ava, came home from school unusually quiet one day. When I pressed her, she finally confessed: a new teacher was constantly humiliating her in front of the entire class. The teacher repeatedly told Ava she wasn’t “very bright” and lacked the intelligence to succeed.

Ava begged me not to intervene, terrified that drawing attention would only make the bullying worse. I reluctantly agreed to wait, but the situation deeply unsettled me—because it mirrored my own painful experience in middle school. When I was 13, a cruel teacher named Mrs. Mercer told my entire class that “poor girls like me would grow up to be completely broke and embarrassing.”

Weeks later, the school announced an upcoming charity fair. Ava dedicated her evenings to sewing reusable tote bags from donated fabric to raise money for winter clothing drives. On the morning of the fair, I was stunned to discover that the faculty coordinator was Mrs. Mercer—the same woman who had tormented me 20 years earlier.

At the charity event, Ava was proudly displaying her handmade bags when Mrs. Mercer approached our table. She leaned in and maliciously whispered, “Ava has cheap standards and produces cheap work, just like her mother.”....