The Ontario government has updated the province's sexual-education curriculum, a move that been applauded by some and opposed by others. Here are five things to know about the new program:

What does the new curriculum look like?

It will teach students in Grade 1 the proper names for body parts. Grade 2 students will learn about the broad concept of consent by being told that no means no. Concepts of gender identity will be introduced in Grade 3, though the curriculum doesn't get explicit and positions sexual orientation as one of the potential qualities that distinguish people from one another.

Discussions about puberty move to Grade 4 from Grade 5, while education about intercourse will take place the following year. Masturbation and "gender expression" will be taught in Grade 6, while kids in Grades 7 and 8 will discuss contraception, anal and oral sex, preventing pregnancy and sexually transmitted infections.

Students will also learn about online bullying and the dangers of sharing sexually explicit images electronically.

Who opposes the curriculum and why?

Some of the objections come from religious groups who claim the curriculum doesn't align with their values. Some parents have also accused the government of failing to allow them enough input into the development of the new curriculum. Criticism around the gender identity portion of the program has been particularly contentious in light of the fact that Premier Kathleen Wynne is openly gay. Wynne called some of the criticism "homophobic."

What do the other provinces do?

Ontario hadn't previously updated the curriculum since 1998 and argues that the changes are necessary to bring sexual education in line with other provinces. By teaching concepts around sexual orientation and gender identity at an early age, it joins the ranks of Quebec, Saskatchewan and Nova Scotia. At least four other provinces choose to tackle the issue in Grade 6 or beyond. Concepts like consent, contraception, prevention of sexually transmitted infections and online safety appear on nearly every provincial curriculum. Some provinces begin teaching these concepts as early as kindergarten.

When does it kick in?

Education Minister Liz Sandals has said that the new curriculum will go into effect this September.

Is it mandatory for all students?

No. Parents have the right to withdraw their kids from all or part of the new curriculum if they're uncomfortable with its content.