If someone told you that the funding your school receives bears no relation to its actual costs, you might not be too surprised.

Most people working in schools have felt the increasing pinch between what they want to do and what they can afford.

It’s more surprising, though, when you realise this is by design, not by accident.

The way schools are currently allocated funding is incredibly complicated: a mix of fixed amounts, per-pupil funding, top-ups and special grants. Some elements are set nationally only to be tweaked by local councils. Many come with strings attached and potential clawbacks if certain targets aren’t met.

Some crucial factors - like teacher and support staff pay levels - are regularly only decided months after budgets are set.

In short, funding long since stopped being linked to actual costs, instead being the product of year after year of spreadsheet manipulation, formula tweaks and arbitrary adjustments.

Time for change

This week, after a year of consultation with academy trust leaders across England, the Confederation of School Trusts (CST) has called time on this and put forward plans for an overhaul of how that system works.

Our focus is not on just calling for more spending, although we need that too.

Research CST commissioned from international economic consulting firm Compass Lexecon makes a clear case for increased investment in education.

Their analysis found spending on education has significant benefits to society, way beyond the initial spending: a long-term increase of 10 per cent in spending on primary and secondary education across the UK over the next 50-plus years would cost an average of £17 billion a year, but reap £95 billion in benefits to the economy.

That is before associated benefits like improved physical and mental health, reduced crime rates and enhanced civic engagement.

Fairness and transparency

Even without that, simply changing how the government hands out money to schools could offer significantly increased fairness, transparency and stability, allowing school leaders to plan ahead and better tackle long-seated challenges like failing buildings and the lack of special educational needs and disabilities (SEND) provision.

Right now, funding is too unpredictable, is not calculated against the actual costs facing schools and has failed to keep up with moves to a trust-led system.

We are calling for a fully implemented national funding formula (NFF) for all schools, including special settings and alternative provision, that integrates long-standing additional funding such as the pupil premium, so schools are adequately resourced to deliver the education provision society expects and children deserve.

The gradual transition from local to national formulas was intended, rightly, to prevent cliff-edge changes to funding but its slow and unpredictable progress now just serves to provide additional uncertainty for trusts trying to plan ahead for future years.

SEND support evolution

We also think there needs to be a new approach to how we think about and how we fund SEND and alternative provision, with a protected minimum level of funding provided through the NFF and additional funding provided for ambitious, tailored provision, rather than a statement of need.

Much of the current funding for our buildings comes from annual bidding rounds, where trusts compete against each other for a too-small pot, or rebuilding programmes that would take centuries to refresh every school.

We need holistic capital funding that is sufficient to meet an ambitious national plan for the maintenance and improvement of the school estate. It should be funded separately to the core delivery of education so that every school is a safe and sustainable place to learn.

The start of a journey

Finally, we know that circumstances change - and policy priorities come and go.

To address both, the final element of our funding reforms is a policy premium mechanism, to provide a standing route for genuinely time-limited additional funding beyond the three main funding streams (like a guaranteed uprating of pay and pension changes, including minimum and living wages).

There is much more work to be done, by CST and others, in developing proposals for funding reform.

In particular, we think early years and post-16 funding warrant much more consideration, and we want to find solutions for contextual challenges such as those facing small schools or those in private finance initiative contracts, but these four proposals begin to address the complicated web of dependencies - and deficiencies - in the current approach.

Together, we believe they would help trust leaders plan with much more confidence, and with clear links between the work schools do and the funding they receive.

Samuel Skerritt is director of public affairs and policy at the Confederation of School Trusts, the national sector body and membership organisation for academy trusts

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