The unidentified girl wrote the letter to her primary school teacher after a class discussion about why homophobic bullying is wrong.
"Almost every one of my class put their hands up. I was stunned," he said.
When he followed this up by asking who thought that people who were gay or lesbian were bad or wrong in some way, he was again answered with almost every child raising their hand.
"As a primary school teacher I'd always worried about mentioning my sexuality," the teacher explained. "Despite the fact that my colleagues talked about their husbands, wives and significant others all the time.
"After speaking to my Head, who was very supportive, we agreed I could tell the class that I'm gay so they at least knew one gay person and hopefully explain that when people use that word they're talking about me.
"The reaction was fantastic – there were a lot of gasps and shocked looks and some basic questions – do you have a boyfriend, etc. – but after a couple of minutes they were over it and we moved on to the rest of the lesson."
A couple of days later, a girl in the teacher's class handed him a letter at the start of the day when he was collecting slips about dinner money, school trips and doctors appointments.
The letter read: "Dear Mr R,"Even though you're gay, I will always treat you the same way as I do now. I still think about you the same way as I used to. You're a great teacher and these are just some of the words that I would describe you as: great, amazing, fantastic, brilliant, awesome and brave.
The reason why I say brave is because you shared a personal secret which was very brave.
"You don't have to feel scared because I know that everyone in the class feels the same way as I do.
"From A x x
"PS. We are all proud of you."
"Reading it brought tears to my eyes and it took me a little while to compose myself," the teacher said. "When I thanked her she just shrugged and repeated something one of the boys in the class had said during the lesson, 'It's just your life'. Then she went back to her maths.
"I've had a lot of letters and cards over the years, but this one I know I'll keep forever."
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