A MAJOR argument against same-sex marriage from the No campaign is that such a law could change Australian classrooms.
The Coalition for Marriage says legalising gay marriage would open the doors to make anti-bullying program Safe Schools mandatory in schools.
The program is aimed at making schools safer and more inclusive for LGBTI students, staff and families - but some say it teaches radical and age-inappropriate ideas.
So would a Yes vote in the same-sex marriage survey make Safe Schools mandatory? And what exactly does the program involve?
We looked at the facts and fiction around the issue.
CLAIM: Safe Schools introduces children from primary age to inappropriate sexual concepts
Safe Schools Coalition Australia offers resources on issues affecting LGBTI students and the school community, including identity, ethnicity, drugs, alcohol and mental health. The program is run in just 307 schools nationwide.
Materials are targeted at different age groups - primary age students focus on cultural diversity, relationships with friends and teachers, inclusivity and bullying. There is only one resource aimed at supporting gender diverse students, All of Us, designed for secondary teachers.
Most of the concerns around Safe Schools focuses on content created by an organisation for LGBTI teens called Minus18.
When Safe Schools Coalition Australia was reviewed by the Federal Government in March 2016 and taken over by the Foundation for Young Australians, it cut ties with this group.
It also cut ties with Safe Schools Coalition Victoria, which is now run by the Victorian Department of Education and Training.
The Victorian program only uses materials designed by the education department, but remains affiliated to Minus18 and links to some of its material on its website, including OMG I'm Queer, which encourages inclusivity and discusses issues around sex in a frank manner.
The department emphasises these materials are not part of Safe Schools and it is up to schools and teachers how they teach subjects.
CLAIM: Safe Schools encourages students to cross-dress and encourages kids to use different toilets
Campaigner Cella White recently expressed concerns about her daughter potentially sharing bathroom facilities with members of the opposite sex.
All of Us, the national resource for teachers on gender diverse students, does suggest schools supporting a young person transitioning in their gender identity could consider how inclusive its dress code or uniform policy is.
It suggests schools could allow a student to wear "elements of the uniform they feel most comfortable with" and consider which toilets, changing rooms and showers are most appropriate based on the student's gender identity and where they feel comfortable.
The decisions on this are up to the school, in conjunction with students and their parents. Cross dressing and using different toilets are not subjects that are taught or encouraged as part of Safe Schools.
A Safe Schools Coalition Australia spokeswoman said the All Of Us unit guide was written by education experts. "If teachers decide to use this resource, school leadership must obtain consent from the relevant parental body," she said. "We do not advocate for specific policies, but instead work with teachers to build a safer, more inclusive environment for their students at school leadership's discretion."
CLAIM: Safe Schools teaches "chest binding" and "penis tucking"
The article criticised by the Australian Christian Lobby for discussing healthier and safer chest-binding was published on the website of Minus18, a partner of Safe Schools Coalition Victoria. It is not taught in schools.
The article is aimed at teenagers coping with gender dysphoria.
CLAIM: Safe Schools encourages kids to role-play same-sex relationships
Coalition for Marriage spokesman Dr David van Gend says "the All of Us resource has, as its second lesson, Year 7 kids role-playing same-sex relationships" - a claim backed by pastor Heidi McIvor in an anti Safe Schools video.
The exercise suggested to teachers is aimed at developing an understanding of "being different" and what it feels like to have to hide part of yourself. Students are told to imagine living in a world where having teeth is considered unpleasant. They then try talking while hiding their teeth from a partner. The class then discusses how that relates to LGBTI experiences.
CLAIM: Safe Schools posters show boys wearing dresses
Gender Is Not Uniform is a campaign aimed at supporting gender diverse students in schools. It is accessible on the Minus18 website and is supported by Safe Schools Coalition Victoria,
It does include posters but is not part of the program taught in schools.
Safe Schools Coalition Victoria has also produced a model school uniform policy to make schools more inclusive - it's up to schools how this is implemented.
CLAIM: Safe Schools wants to "integrate gender theory and sexual themes across all subjects"
The All Of Us resource was developed to support existing health and physical education curriculum in Years 7 to 10. It states that schools may choose to adapt and use the videos and teaching activities in other areas of the curriculum such as English, History, Humanities, Legal Studies, Civics and Citizenship "where the exploration of LGBTI people and topics allows students to explore a range of areas which are relevant to each subject's learning intentions."
CLAIM: Safe schools could become mandatory if we vote to legalise same-sex marriage
Coalition for Marriage spokeswoman Monica Doumit says such programs were optional in Canada before same-sex marriage was legalised, but have now become mandatory, even for religious schools. "In the UK, faith-based schools that refuse to teach homosexuality and gender identity issues are being faced with closure," she said.
Minister for Education and Training Simon Birmingham says suggestions changing the Marriage Act would see a wave of reform sweep the country was "ridiculous", adding: "This is just not going to happen."
He assured faith-based schools their teaching would be unaffected by the plebiscite outcome. "Schools in the future, if they are faith-based schools, will be able to teach according to their faith and including according to the definition of marriage according to their faith," he said.
CLAIM: Parents don't have a say
Ms Doumit says changing the Marriage Act would mean parents "won't have a leg to stand on" if they "don't want their kids taught radical sex education and gender ideologies".
The national program actually ceased in New South Wales and South Australia in June.
The Victorian program does not impose specific requirements for student participation but asks school community members to demonstrate the school's values. The education department encourages parents to discuss any concerns directly with the principal. "Within any school community there is always a diversity of views represented and schools take those views into account when working with children and families," it says.