An ex-top trustee of Manhattan’s elite Spence School says she yanked her daughter out over her growing disgust with its racial indoctrination — capped by a class video that “tarred and feathered’’ white women. Hispanic tech exec Gabriela Baron fired off a scorched-earth letter to the prestigious Upper East Side institution last week seething that the video — shown to her eighth-grade daughter and classmates on graduation day — “openly derides, humiliates and ridicules white women. “They sat there in their graduation dresses while the white mothers of the white students – many of whom volunteer, donate, call, email and do whatever the school asks of them – were tarred and feathered in a video their teacher showed them. While their white female teachers were mocked,’’ Baron raged in the missive, a copy of which was obtained by The Post. Baron said the footage, featuring racially charged comedian Ziwe Fumudoh, was just another indication of what she and her husband “see happening at Spence (and many other schools in NYC). “Over the last several years my husband and I have grown increasingly concerned about certain trends at Spence, including what we believe is a de-emphasis of academic rigor and a single-minded focus on race, diversity and inclusion that is now driving the School and everything that goes on within its walls,’’ wrote Baron, the daughter of Cuban immigrants.