A teacher who taught controversial sex education classes that included cartoon videos on masturbation for first graders at the posh Dalton School has resigned, The Post has learned.

Justine Ang Fonte, who also taught a one-day workshop on "porn literacy" to juniors at Columbia Grammar & Prep School last month that angered some parents, will not return to the school next year, according to an email Dalton’s head of school, Jim Best, sent to parents Friday. Best also will not be returning to Dalton next year.

"Throughout her tenure at Dalton, Justine Ang Fonte has helped to develop an exemplary K-12 Health and Wellness program. Dalton — our faculty, staff, administration, and trustees — continue to stand firmly behind this program and those who teach it," Best wrote.

"At faculty and staff meetings this week, Justine announced her decision to leave Dalton to focus on her work as an independent Health Educator. She has been working toward this goal for over a year. We support Justine’s aspirations and look forward to honoring her accomplishments as the academic year comes to a close."

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Fonte is the third high-profile Dalton staffer to leave the school this year as the school struggles with a simmering conflict between the faculty and parents over its progressive agenda.

Domonic Rollins, the school’s director of DEI ("Diversity, Equity and Inclusion"), left in February to "pursue other opportunities," the school said at the time. 

Best, Dalton’s headmaster for the past three years who has been with the school a total of 16 years, announced in April he was resigning to pursue "other exciting and inspiring opportunities."

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One parent said Friday she was not impressed with the school’s statement about Fonte. "This inability to admit a mistake or acknowledge a misstep is strange," she said. "It shows a real lack of emotional intelligence and self-awareness on behalf of the leadership team."

Last fall, Dalton parents, who pay $55,000 per year for their kids’ tuition, learned that first-graders were being taught sex-ed lessons that included cartoons showing little kids talking about "touching themselves" for pleasure.

Click here to read more on the New York Post.