Teachers should not be policed by “self-appointed moral guardians” or be forced to change the way they teach in the face of “militant activism”,  the chief inspector of Ofsted has warned.

Amanda Spielman told the Festival of Education today that while activism that broadens debate and brings about long-term change was welcome, she worried about the “militant kind of activism that demands immediate adherence to a position”.

The chief inspector described a “newer phenomenon” of a “particularly confrontational brand of activism”, which she said was “problematic” for schools. She warned that confrontational approaches “both outside and inside schools” were affecting staff, parents and children “and can have a limiting effect on education”.

Spielman said the protected characteristics enshrined in the equality act “don’t always exist in harmony”, and the “conflict between them cannot be entirely neutered by legislation”.

She said children should not have to “cross what amount to picket lines outside their school because one group’s religious beliefs – protected by law – sit uncomfortably with teaching about another group’s sexuality – also protected by law”.

It also can’t be right that the curriculum “can be filleted by pressure groups”, Spielman said, as she warned that the “militant defence of orthodoxies” was “not confined to adult protests, or to the protected characteristics”.

The Ofsted boss said there was more pupil activism in schools, but in some cases children and teachers were “suffering abuse or even violence, simply for being who they are: for being the wrong religion, or race, or ethnicity”.

Amanda Spielman

“This is completely unacceptable. And nor should children be all but forced to support a fellow student’s campaign, no matter how compellingly presented, nor feel that they will be ostracised if they do not.”

However high feelings run on an issue, “the correct response of a school should surely be educational”, Spielman said.

“Let’s not have teachers policed by self-appointed ‘moral guardians’ who refuse to tolerate an alternative viewpoint. Or harried on social media into apologising for what they’ve said, or into changing the way they teach, in the face of militant activism.”

She warned social media could be a place of “groupthink, intolerance and bullying”.

“It fosters and then feeds off tribalism – whether in politics, or in social attitudes. It encourages people to run with their herd, feeling at home in the company of likeminded types. Education should never fall into the same trap.

“Campaigners often aim to convince us that in a complex world full of difficult challenges and multi-faceted problems, there are simple solutions to enact. But to educate our children properly, we shouldn’t pretend this is true.”

Watch Amanda’s speech at the Festival of Education here: