Today, along with more than 1,000 other people, I’m heading to the Houses of Parliament.

This is no half-term outing. It’s a mass lobby organised as part of the joint union School Cuts campaign - a chance for parents, school staff and headteachers to meet MPs and outline the urgent reality of the funding crisis facing our schools and colleges.

This isn’t scaremongering. Education funding is facing its biggest shortfall in a generation.

Independently verified analysis by the likes of the Institute for Fiscal Studies and the Education Policy Institute verifies that - at a time when the expectations of our education system have never been greater - the funding downturn is taking us back to budgets which in real terms have not been seen since the mid-1990s.

As a head or principal, you know the relationship between funding and provision - the cost of staff, of class sizes and the endless juggling between principles and pragmatism. This is a core part of the job of any school or college leader. You work with your curriculum planner, chair of finance and business leader to ensure the best provision for young people at the optimal cost.

The £2.8bn hole in our budgets

But none of us has faced anything like this - a context in which a repeated failure to increase school budgets to keep up with inflationary pressures, and rises in employers’ contributions to national insurance and teachers’ pensions, together with the removal of specific grants, has effectively created a £2.8 billion hole in school budgets since 2015.

Recent figures show that more than 9,400 schools - over one third of state schools - were in deficit in 2015-16. Almost 4,000 of them have been in deficit in each of the past two years, with almost 1,600 in deficit three years in a row.

Having made all the efficiencies you can on procurement, and now faced with the need to make further savings of, say, £100,000 next year, you cannot achieve that by postponing the painting of a few corridors, or putting on hold some orders for new textbooks.

The only way to make those savings is by directly impacting on the education of young people ­- increasing group sizes, reducing curriculum choice for students, and even removing some subjects from the curriculum in order to reduce staffing costs. It really is the only option.

As a professional association representing the nation’s educational leaders, the Association of School an College Leaders understands the scale of the issue and its human impact. I know from our telephone hotline that our members are wrestling with tortuous decisions as they have to cut provision and restructure to reduce staff numbers, and that they feel a growing sense of dismay at the decisions that have to be made.

But we also know that the Department for Education is alert to the scale of the problem. Before the summer holiday, we saw that education secretary Justine Greening’s accountancy credentials enabled her and her team to do some creative and much-welcomed shifting of funds from obscure parts of the education budget to the frontline for classrooms.

This sent out a strong signal. Now it’s time for the Treasury to act. Because ultimately, today’s lobby of Parliament isn’t just about money. It’s about principles. It’s about whether one of the world’s richest economies values education enough to fund it properly.

Vulnerable children ‘most at risk’

It’s about social justice, too - because faced with having to cut courses, it is the education of the most vulnerable that is most at risk. It means that on the watch of a government that talks about helping the disadvantaged, it is those very children who are likely to find themselves with the least access to modern foreign languages, drama, music, the arts in general - and all the other provision that ought to be the entitlement of every child from every background.

So this explains why the lobby of Parliament matters so much, and why it has gained such support. It explains why unions and associations from across the spectrum are uniting to campaign along with parents and governors.

At ASCL, we have a powerful mission statement: ‘We speak on behalf of members; we act on behalf of children and young people.”

Today, all those of us who head to Parliament will be doing just that - acting on behalf of children and young people.

Geoff Barton is general secretary of the Association of School and College Leaders. He tweets @RealGeoffBarton. 

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