Wynne, who is openly gay, took issue with a comment from Progressive Conservative Monte McNaughton, who has frequently criticized the premier's "sex-ed agenda."
"It's not the premier of Ontario's job, especially Kathleen Wynne, to tell parents what's age-appropriate for their children," McNaughton said Monday following the release of the new document.
Wynne demanded that McNaughton explain why he feels she is not qualified to set education policy.
"Is it that I'm a woman? Is it that I'm a mother? Is it that I have a master's of education? Is it that I was a school council chair? Is it that I was the minister of education?" Wynne said Tuesday in the legislature.
Education Minister Liz Sandals said after question period that McNaughton has made remarks "that are quite homophobic."
McNaughton said Wynne's suggestion that he's homophobic is "the lowest thing a premier of Ontario could say about any other legislator."
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Sandals, in question period, suggested McNaughton wouldn't just "opt out" of sex-ed, but also teaching evolution if he were premier, to which Progressive Conservative Rick Nicholls shouted, "That's not a bad idea."
Meanwhile, outside the legislature a few hundred people protested the sex-ed curriculum, with some saying parents were not consulted enough, many complaining about masturbation being mentioned in the Grade 6 curriculum, while a few espoused more extreme viewpoints.
Speakers at the rally included McNaughton and fellow PC leadership contender MP Patrick Brown.
"Teachers should teach facts about sex education, not values," Brown said. "Parents teach values."
A spokesman for the third remaining candidate in the race, MPP Christine Elliott, said minutes before the rally began that she was due to speak, but Elliott did not end up attending. Her spokesman said "there was a change in plans as Christine had legislative duties to attend to." She released a statement saying parents were "shut out" of the curriculum consultation.
Progressive Conservative Interim Leader Jim Wilson said any members attending the rally were doing so independently, as part of their leadership bids.
Other speakers at the rally included members of the anti-abortion group Campaign Life Coalition, the Catholic group Parents As First Educators and several parents. Claudia Rulli, a mother of two, said the curriculum "pushes sex" and called for it to be scrapped entirely.
"In protecting my children, premier, you do not have my consent to teach my children about masturbation, oral and anal sex, and you do not have my consent to teach them about gender identity theory," she said. "Our message to this government, who wants to manipulate our children into a distorted way of thinking is: Not on our watch."
The curriculum — last updated in 1998 — brings Ontario in line with other provinces, Sandals said.
By Grade 3, students will learn about same-sex relationships. Children in Grades 4 and up will learn more about the dangers of online bullying, while the dangers of sexting will come in Grade 7. Lessons about puberty will move from Grade 5 to Grade 4, while masturbation and "gender expression" are mentioned in the Grade 6 curriculum.
Vincent Chan, a father of two, said teaching kids proper names for body parts in Grade 1 is good, but some of the lessons, such as masturbation, come too young.
"I believe that teaching them sex education is important, but teaching them at such a young age is not appropriate," he said.
Masturbation is included as a "teacher prompt" in the section of Grade 6 curriculum discussing changes that occur during adolescence.
"Exploring one's body by touching or masturbating is something that many people do and find pleasurable," the teacher prompt says. "It is common and is not harmful and is one way of learning about your body."