Where does LGBTQ fit in the curriculum

With respect to LGBT in our curriculum, it isn't explicitly taught at the elementary level.
In the Health Curriculum it's dealt with in terms of building healthy relationships and bullying.
Building healthy relationships is a key theme of the health curriculum and it starts in Grade 1.  Although LGBTQ relationships aren't named specifically, the focus should be on general points that can be applied to any relationship

The curriculum says:
"In health education, the study of healthy relationships, particularly with respect to bullying/harassment and violence prevention, should include a focus on sexist, racist, and homophobic behaviour"
Bullying is covered throughout the curriculum, but homophobia is covered specifically in the following grades:

Grade 4
describe various types of bullying and abuse (homophobia used as an example)
Grade 5
explain how a person’s actions (e.g., negative actions such as name calling, making homophobic or racist remarks, mocking appearance or ability, excluding, bullying, sexual harassment; positive actions such as praising, supporting, including) can affect the feelings, self-concept, emotional well-being, and reputation of themselves and others
Grade 7
Interpersonal Skills under Healthy  Living: practise effective responses to someone who directs a homophobic or racial slur to them or to another student)

While not mandated by the curriculum, LGBTQ discussions often arise during puberty education.
We currently have an interim edition of the curriculum.  A more comprehensive curriculum which specifically includes more LGBTQ topics is stuck in draft form.