Six weeks is a long time in politics. We know a lot more now about education funding than we did on 18 April, when Theresa May made her election call. Much has happened to clarify the meaning of the parties’ education policies.

This is no thanks to the outgoing government. Justine Greening has conducted herself as if pre-election purdah applies to candidates as much as civil servants: her contribution to the public debate has been negligible. Her party has sought to conceal rather than clarify the meaning of its policies. The Conservative manifesto speaks of a “real-terms increase” in school funding, though in reality 93 per cent of schools will, by 2022, experience a real-terms per-pupil spending cut.

Truth has to be sought not in the manifesto but elsewhere. The Institute for Fiscal Studies calculates that if Conservative spending policies are adopted, there will be a reduction of nearly 7 per cent in per-pupil funding by 2022. Lib Dem pledges would reduce this fall to 4.2 per cent; Labour’s policies would result in a real-terms per-pupil increase of 1.6 per cent.

The IFS calculations are the basis of the figures presented by NUT, ATL, NAHT and GMB on our School Cuts website. They enable an authoritative challenge to highly misleading claims. But the website goes further than this. It digs deeper than any national analysis has previously been able to do.

Using other data to complement IFS figures, it shows the projected effect of Conservative, Labour and Lib Dem funding policies on every school in England and Wales. It employs a rigorous methodology with assumptions and procedures made absolutely transparent. It brings to the debate a focus and a clarity that are totally absent from the programme of the governing party.

Spreading the message

This is work that is reaching a huge audience. The website has been visited 600,000 times. The NUT’s Facebook video on education cuts, released on 27 May, has already been viewed 3.7 million times and shared by 77,000 people. Thousands of volunteers have signed up to distribute the campaign’s leaflets.

Something is happening here of great significance - the emergence of a constituency that extends well beyond the teaching profession, and that is well-informed and active on key questions of education. As Newsnight policy editor Chris Cook acknowledges, the campaign is “getting a clear message across to ordinary voters”, with the result that “all UK-wide parties have been encouraged to make financial pledges”.

Whatever the outcome of the election, this new way of working will have a lasting effect on education policy debate.

We are now able to translate the words of politicians and the claims of manifestos into direct predictions of the funding consequences for every school. We are developing the capacity to make these issues the subject of ordinary politics - the things that parents will talk about at school gates.

From now on, this is what we will do in every election, and we invite politicians when they are drawing up their funding policies to test them against the methodology developed in the campaign.

A significant step

This would be accountability in action - democratic accountability. For teachers, for whom “accountability” has long signified a punitive and damaging experience of political bullying, it would be a sweet riposte. For parents, it would promise an end to the careful equivocations of party spokespeople, pledging - like David Cameron in 2015 - to “protect school funding” while meaning something very different.

Six weeks, then, is a long time: long enough to challenge and change the ways that education policy is formulated and debated; long enough to raise the standard of argument to the point where politicians cannot any longer get away with fanciful claims, lazily repeated.

This is a real shift in political culture, and I am proud of the way my union is contributing to it.

Kevin Courtney is general secretary of the NUT teaching union.

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