“Catastrophic” rather than “historic” is the message from an Islington headteacher on the government’s latest school funding reforms.

Education secretary Justine Greening unveiled the details of the new national funding formula last week, with schools getting an increase of 0.5 per cent per pupil from the next school year, and a 1pc increase from 2019-20.

However, due to inflation pressures, Labour MPs have pointed out that the funding formula still represents a “real term cut in school budgets”.

Under the government’s original proposals for the formula, revealed in December, funding for Islington schools would have been cut by £15million by 2019/20. This translated to £711 less per pupil – or 400 fewer teachers across the borough.

It sparked a wave of protests in Islington and in May, hundreds of staff, students and parents flocked to the borough’s parks – including large representations in Finsbury Park and Tufnell Park – to take part in “protest picnics”.

In the same month headteachers and governors from 51 Islington schools signed a joint letter calling on Ms Greening to reconsider her proposals.

Teachers and students also came up with unique ways of expressing their ire.

Cassie Moss, headteacher of Yerbury primary school which recorded the anti-cuts anthem and video Schools Just Wanna Have Funds, said: “Ms Greening’s plan will be catastrophic for many schools – 90 per cent of them still lose out in real terms and schools will have no other option than to look at reducing provision for the children.

“That may be in the form of cutting resources, additional support or staffing, but for many schools, with the national funding formula plan announced as it was, it’s likely to be all three.

“It’s totally unsustainable.”

In a reform she described as “historic” and one that addressed the “inequities in funding that have existed for far too long”, Ms Greening is increasing the basic level of funding to at least £4,800 per pupil at secondary schools in England, as announced in July, and £3,500 per pupil at primaries.

Despite some welcoming the extra cash for schools, others claim the announcement does not make clear what happens after 2019-20, or what will be cut from the Department for Education’s budget to fund the extra £2.6bn promised by Ms Greening.