Ontario Premier Dalton McGuinty, shown earlier this year at a school in Windsor, says the sex education curiculum revision needs to be reconsidered. (Canadian Press)

A controversial new sex education curriculum that would have seen Ontario children learn about sexual orientation in Grade 3 and masturbation in Grade 6 will be postponed and reworked, Premier Dalton McGuinty said Thursday.

It's obvious from listening to parents over the past two days that the curriculum needs a "serious rethink," McGuinty said after an unrelated event in London, Ont.

"We'll take the [sex ed curriculum] we had proposed putting into place back off the shelf," he said.

The government, McGuinty added, will "create more opportunities for parents to lend shape to a policy with which they are more comfortable."

"I know that parents are supportive of the idea that children should be taught about their body parts, relationships and those kinds of things," said McGuinty. "But they are obviously not comfortable with the proposal that we put forward, and so we are going to improve upon that."

The existing sex ed curriculum, which hasn't been updated for 12 years, will remain in place, he said.

The proposed changes outraged some religious and conservative groups who say they're not comfortable with teaching kids as early as Grade 3 about same-sex families.

Under the changes that were quietly released in January, Grade 1 children were to be taught to identify genitalia — among other body parts — using the correct word, such as penis, vagina and testicle.

In Grade 5, children were to be taught to identify parts of the reproductive system and describe how the body changes during puberty.

In Grade 7, the plan was to teach kids how to prevent unintended pregnancy and sexually transmitted infections, including HIV.

NDP education critic Rosario Marchese said the government's sudden about-face shows the Liberals are overly sensitive to the criticism from certain groups.

"I'm disappointed he backed down so quickly," said Marchese.

"I'm worried about the fact that yesterday the premier said 'we're forging ahead because we think we're doing the right thing' and a day later he's saying 'we made a mistake, we should have consulted better' .... Based on this problem I think the premier should consider going to confession," said Marchese.

Marchese said the NDP supports sex education in schools but believes parents should make the final decision about when it's taught. "There is room to talk with parents about when it should start ... we believe parents are the final arbiters of these moral decisions."

The government's about-face has pleased representatives from the Canada Christian College, who said they are "thankful that the premier has come to his senses," CBC's Marivel Taruc reported Thursday.

With files from The Canadian Press