Pupils at Parkfield Community School, where 99 per cent of students are Muslim, are educated about same-sex couples through story books, in a programme named “No Outsiders”.
Andrew Moffat, the school’s assistant head, leads the programme and has been targeted with protests and threats in recent weeks.
They have argued that the classes are against their religion.
“The whole school approach ensures your child’s personal development as well as their academic development,” the trust said.
“It is also essential that pupils are prepared for life in modern Britain.
“The weekly protests are upsetting for all, disrupt the normal routines of the school and will have an overall effect on the educational achievement and wellbeing of your children.
“We therefore appeal to you to stop the weekly protests.”
Mr Moffat, who is gay, has received threatening emails over the lessons and believes his openness about his sexuality triggered the controversy.
“I am a teacher that just so happens to be gay. I should be able to teach safely and comfortably anywhere,” Mr Moffat previously told The Independent.
Adults with megaphones shouted “Get Mr Moffat out” at one protest.
The teacher is a top 10 finalist for the million-dollar Varkey Foundation Global Teacher Prize, one of the world’s top teaching awards.
Despite the protests, some parents have expressed their support for Mr Moffat’s lessons.
“Many parents have approached the school in the last few weeks to express support for the No Outsiders ethos and to say they understand what No Outsiders is about, and why it is important to teach children about difference in the UK,” the Excelsior Multi Academy Trust said.
The school will arrange a series of meetings over the next few months to discuss the programme with parents.
Mr Moffat said that pupils at the school had rallied around him through the controversy.
“I was inundated with little posters and cards that children had made at home saying, ‘No outsiders. Everyone is welcome,’” the teacher said.
“The first one I got I was quite shocked.
“I asked the eight-year-old girl why she had done it. And she said: ‘Because people are being unkind about you and I thought it would cheer you up.’”
The teacher has no plans to leave the school.
“As educators we have to be very clear how we respond to a potentially divisive society,” he previously told The Independent.
“Schools can be the agents for change. We can be the ones that make society cohesive.”
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