The recent protests outside some primary schools in Birmingham bring back painful memories for me of some 30 years ago. At the time I was teaching in a large comprehensive school and in a relationship with another female teacher. This was when same-sex relationships were little acknowledged and we knew very few other same-sex couples, so we were already quite isolated. It was then that Margaret Thatcher’s government introduced the homophobic law Section 28, which stipulated that local authorities must not “promote homosexuality” or promote “the acceptability of homosexuality as a pretended family relationship”.

This language was hateful, threatening and intimidating, and I was conscious that the force of the law could be used against me. Back in 1988, there were no anti-discrimination laws that covered a person’s sexual orientation, meaning that you could be fired just for being gay.

All of this made it very difficult for gay teachers to be open about their sexuality, thus losing valuable opportunities to provide positive role models to young people. It undoubtedly delayed my own coming out and I just got into the habit of never mentioning anything at all about my personal life to anyone at work.

But perhaps the worst thing about that law, and the fear that it instilled in gay teachers like me, was that it made it impossible to challenge homophobic bullying effectively. At the time, homophobic insults in the classroom were commonplace, making the lives of many students a misery. Yet if you had called out these comments as homophobia, you risked being accused of “promoting homosexuality” and marched off to the headteacher’s office. When a pupil made a homophobic remark, I did not want it go unchallenged, but all I could manage was something feeble like, “Don’t you think that could be a bit hurtful to some people?”

If the classroom was hard, the staffroom was even worse, especially trying to challenge male teachers exchanging homophobic “banter”. Some colleagues were already quick to mock me as a “leftie feminist”, so could I risk the suspicion of being gay when that could be used against me in my employment? And so, yes, I am ashamed to say I did let comments go unchallenged. I could have, and should have spoken up, and I am immensely grateful to all those who were brave, did speak up and helped society to become more accepting of LGBT people.

That’s why I feel so passionately that we must now further that process and ensure that it is absolutely the norm for LGBT issues to be part of the curriculum. Because far from protecting students from being exposed to harmful material – as some parents in Birmingham have claimed – all we achieve when we censor any discussion of LGBT relationships in schools is guaranteeing that children who are coming to terms with being gay are left feeling isolated and alone.

Of course teachers are there to educate their students, but they can also support them through difficult times. Research by Stonewall shows that nearly half of LGBT pupils today are bullied for being LGBT, and we know the lasting damage that can cause. I would hate us to go back to a time where teachers become bystanders to this abuse, more concerned about a minority of parents than with the wellbeing of the children in their care.

Moreover, with many same-sex couples choosing to have children of their own, it is a fact of life that there are pupils in many classrooms who have two mums or two dads. And so it is very distressing to me that anxiety is being whipped up amongst some groups of parents, and that some politicians – including candidates for the Conservative leadership, and even some in my own party – are indulging this bigotry and prejudice.

Quite possibly the younger generation of teachers are more at ease with talking about sexuality than many of my contemporaries, but they need to know that they have our full support, not just the letter of the law. We owe it to today’s young people and the teachers who are delivering LGBT education to give them our full backing and ensure that there is no back-sliding on this important step towards creating a genuinely inclusive society.