School funding has risen, fast, up the political agenda. School leaders, in their desperate attempts to balance their school budgets, are thinking the previously unthinkable as they consider narrowed curriculums, reduced subject choices, larger class sizes, making teachers and teaching assistants redundant, even shortening the school day.

But there is a danger, in all the furore, that education professionals may take aim at the wrong target. The proposed national funding formula (NFF) is not the problem that is causing the crisis in school budgets. In fact, the formula is progressive - remarkably so for a Conservative government, giving greater weight to pupil deprivation (up from 7.6 per cent to 9.3 per cent), to low prior attainment (4.3 per cent to 7.5 per cent) and English as an additional language (0.9 per cent to 1.2 per cent). Under the formula, 44 per cent of pupils in England’s schools will be awarded extra funding because of the formula’s deprivation factors.

It is this greater emphasis on deprivation which has angered f40 - the group of the lowest-funded local authorities. It has written to Theresa May arguing that “the proposals direct too large a proportion towards deprivation”.

That is, of course, a view which the f40 is entitled to hold. The problem is that the evidence does not support it. The Social Mobility Commission 2016 report should make us face the unpalatable fact that, in the UK, in 2016, pupils’ educational achievements were overwhelmingly dictated by the circumstances of their birth. The UK has the world’s fifth largest economy and yet 2.3 million children are officially classified as poor. Inequality begins at birth and grows with the child.

The stats are shocking: social class is a major determinant of school readiness - and in the past decade half a million children were not ready for school aged 5. As the commissioners noted, the link between social demography and educational destiny has not been broken: over the past five years 1.2 million 16-year-olds - disproportionately from low-income homes - have left school without five good GCSEs. The effect on educational performance caused by an income gap is larger than that for either the ethnicity gap or the gender gap in schools.

So, I have no problem with the proposed funding formula’s weighting for deprivation. Poor pupils need significantly more support, in school, to achieve their potential - and providing this support adds to schools’ costs. If the f40 argues that there should be less money for deprivation, it needs to show how poor children will be supported to achieve their potential in the way that their more economically advantaged peers already do. Quite simply, the current situation of educational achievement being determined by deprivation cannot, and should not, continue.

‘Don’t blame the new funding formula’

The f40 should be directing its ire against the overall funding settlement for England’s schools, rather than the proposed funding formula. Despite the government’s protests that it is now spending more than ever on schools, stubborn facts remain. At the same time as pupil numbers are rising rapidly, school leaders are being required to make £3 billion of “efficiency savings” - equating to an 8 per cent real-terms cut in school funding. So inadequate is the funding settlement that even the paltry rises in teachers’ pay, along with increased national insurance costs and pension contributions, are proving to be the straw that breaks schools’ backs in balancing the budget.

The funding gap is compounded by the government’s incompetence. A recent National Audit Office (NAO) report revealed that, although the Department for Education had a list of the policy reforms it required schools to implement, it had no idea how much these reforms would cost. As the NAO noted, in some bewilderment: “The department compiles a list of future policy changes that it expects will affect schools but has no plans to assess the financial implications for schools of these changes. It does not therefore have assurance that its policies are affordable within current spending plans without adversely affecting educational outcomes. It leaves schools and multi-academy trusts to manage the consequences individually.”

And while schools are left to their own devices, searching desperately for ways to balance their books, watching their buildings deteriorate and their resources dwindle, the Education Funding Agency purchases land, and buildings, at hugely inflated prices, to build free schools - often in areas where there is no need for extra places.

Theresa May’s government showed that it is not infallible in its judgements of what the electorate will accept as just and fair in its botched Budget, which announced rises in national insurance for self-employed workers.

When it comes to education, the Budget announcement of £320 million to create free schools, some of which might be selective, will come back to haunt the prime minister. As existing schools feel the full brunt of inadequate funding, and as the effects become clear to parents, local MPs will come under increasing pressure - which they will heap upon government ministers.

In the meantime, my advice to school leaders is do not hide from parents the choices you are having to make. Be clear where the cause of the problem lies - and work with parents, governors, unions and other stakeholders to campaign for a fair funding settlement for schools.

It takes some time for education to rise up the political agenda in the way that the NHS does so regularly. We should not waste it by aiming at the wrong target.

Dr Mary Bousted is general secretary of the ATL union. She tweets as @MaryBoustedATL

For more columns by Mary, visit her back-catalogue

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