The contraction of school budgets over the past three years is one of many grave errors of judgment by this government, and has compounded the mistakes of the previous one. That departing prime minister Theresa May now appears to recognise this, and is reportedly seeking a three-year, £27bn funding package before she stands down, does not alter her record. Since 2009, funding per pupil in English schools has fallen by 8%. The predictable result has been worsening conditions all round, but particularly for vulnerable pupils and those with special educational needs who ought to receive additional attention.

Rightly prioritising lessons and teachers over all the other things that schools do, headteachers have instead cut wraparound services such as breakfast and after-school clubs; teaching assistants and support staff; non-core subjects in secondary schools; and budgets for stationery, heating and other items. Given this background, it was not surprising to learn last week that an east London primary has become the latest school to apply for charity funds.

Headteacher Ian Bennett described as criminal the loss of two reading-support workers at a school where 89% of pupils have English as a second language. This is where the grant he is seeking from BBC Children in Need will go. At least 52 other schools already receive Children in Need funding for projects based in UK schools, which the charity says represents 2% of its current portfolio.

Meanwhile, as we reported in April, schools across the country have turned to crowdsourcing websites and wishlists to try to plug holes in sports, maths and music provision, and to purchase supplies. This is all the more worrying when problems with recruitment and retention are acknowledged by ministers to represent a serious threat. It means that when key teaching roles are unfilled, the resources and attention of school managers are being distracted by lack of staff to fill support roles. Such pressures, combined with the well-documented impact on schools of rising poverty, particularly children who are hungry, creates an environment in which school exclusions become more likely.

Schools have always raised funds for extras. There is no reason why those that want to branch out into holiday playschemes, or offer new extracurricular opportunities, should not apply for grants. But schools seeking charitable funding for what headteachers regard as essentials crosses a line, and Children in Need is clear that its role is not to fund statutory services. Education is funded through taxation. For headteachers to be forced to turn to charity feels wrong.

This is particularly the case given that Conservative ministers made a theme of their desire to iron out inequalities in school funding. The government’s new national formula was flawed: budget increases for the worst-funded schools should not have been at the expense of others. It also covered just two years’ cash for schools until 2020. In practice this has meant reduced income and higher operating costs for many schools, undermining calls by the government for schools to improve long-term planning. The sharp rise in school fundraising makes a mockery of any attempt to make the system fairer. Increased reliance on private donations can only increase unfairness.

This has not happened by accident. The Rocket Fund, a crowdfunding platform that holds up private-school fundraising departments as an example to state schools, is a government-sponsored startup. The pitfalls are blindingly obvious: while schools in well-off areas may well succeed in extracting voluntary contributions from parents or alumni, schools in poor areas will not.

In the short term, Children in Need may help to redress this imbalance, even if the inevitable knock-on effect is fewer grants for voluntary organisations such as youth centres. That the entrenched inequality in the English school system – and particularly the funding gap between state and private – continues to grow in the 21st century is a stain on the nation that no amount of charitable goodwill can wipe off.