Last week saw as many as 1.5 million people take to the capital’s streets in a celebration of diversity and equality.

And among those taking part in London Pride 2019 were countless teachers, including groups from the Teach First recruitment charity, and the NASUWT and NEU teaching unions.

Five decades after the Stonewall riots sparked the modern LGBT movement, many revellers will have reflected on the transformation in attitudes across society, but the placards held aloft by NEU members were a sharp reminder that in schools some of this progress is being questioned afresh: “We are here” and “Schools: defend LGBT+ inclusion”.

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The concerns have, of course, been spurred by events in Birmingham since the new year, where noisy demonstrations outside Parkfield Community School, and then Anderton Park Primary, have targeted LGBT content in lessons. And the campaign against the content has spread to many other areas.

Speaking at a packed session at the TUC’s LGBT conference in the two days before London Pride, Sue Sanders, who founded the charity Schools Out UK, warned that it was “a real challenge” for teachers to be out and proud as LGBT. Indeed, she said, “it is probably easier to be out as an LGBT+ police officer than it is as a teacher”.

But amid all this, Parkfield last week planted an important flag of intent.

Months earlier, it had suspended the No Outsiders programme developed by its assistant head Andrew Moffat to allow lengthy consultations with the local community.

It is a programme that saw him hailed as one of the top 10 teachers in the world, and is used by schools across the country. Symbolically, any decision to end the programme would have been a deeply felt blow to supporters of LGBT inclusive education.

Instead, the school has stood firm. It announced that a modified version of the programme, No Outsiders for a Faith Community, would resume in September.

The school said it would acknowledge and respect the “concerns and sensitivity expressed by some parents in the present school community”, but it was clear that lessons would reference gender reassignment and sexual orientation, along with other protected characteristics.

For five months, the school had worked carefully with protesters to try to find a mutually agreed way forward. In this, it did not succeed, with protest organisers rejecting the modified No Outsiders as “heavily biased towards LGBTQ”.

Parkfield will have known that by reinstating the programme, it risked reigniting the protests and disputes, and this week a "small group" of protesters duly arrived at the school's gates.

However by nevertheless choosing to go ahead, the primary sent a clear message that equalities – all equalities – are non-negotiable.

The school’s decision to take a stand is at one with those who want the work started outside the Stonewall Inn in 1969 to be completed.