Open days for Year 11 students considering their options after GCSEs are exciting for families and teachers alike. It is a chance to show what makes one sixth form different from another.

But this year is different. On 1 October school and college leaders received notice that the Large Programme Uplift - funding that recognises the extra teaching time required to deliver the International Baccalaureate (IB) - will be scrapped from next September.

For the schools and colleges I have the privilege of representing, the IB provides opportunity through social and economic mobility.

For half a century a small but important group of state providers have offered this well-balanced, globally respected curriculum to open their students’ minds as well as open doors for them with their next steps.

The benefits of the IB Diploma

What sets the IB Diploma Programme apart is disciplined breadth.

Every student continues with mathematics and a science, a humanity, a language and the arts. Students complete a 4,000-word extended essay, study Theory of Knowledge and undertake sustained community service, preparing them to thrive in university, in their careers and in their communities.

The result is a pipeline of undergraduates, apprentices and employees who are numerate and literate, collaborative and questioning - well-rounded, curious citizens able to apply quantitative skills in real settings, write with clarity, interrogate information and lead with empathy.

Teachers are rightly proud of the specialist provision they have built, and the destinations it secures for young people who do not have the means to pay for it elsewhere.

The preserve of fee-paying schools?

Worth roughly £1,000 per student per year, the uplift underwrites the almost 20 per cent additional taught hours that make the Diploma possible.

Remove it and access to the programme in the state sector is immediately reduced. Schools and colleges simply cannot absorb this cost amid all the other financial pressures they are facing.

All schools are different, but the fact is that school leaders are being forced to make a financial decision when they know that ideologically the Diploma Programme is a prevailing choice for their communities.

If the uplift funding disappears for state providers, the IB will not vanish from England - it will just become the preserve of fee-paying schools.

How exactly the Labour government can square that with its mission to break down barriers to opportunity, I do not know.

Immediate impacts

The government’s rationale is to focus on “high-value” A-level combinations, like science, technology, engineering and maths (Stem) subjects. Whatever the intention, the effect is to penalise the only mainstream route that compels advanced Stem alongside continued study of languages and the humanities.

In one act, the government has imperilled the only recognised qualification delivered in state schools that requires compulsory mathematics and literacy beyond 16.

The consequences have already begun. Tonbridge Grammar School - a high-performing state provider that previously delivered the IB to all sixth-formers - has announced it will regretfully move to A levels from next year because of the funding cut.

I know how tough a decision like this would be to make, not least at this time of year.

Once teams are dismantled and expertise disperses, restarting programmes later would be very tough, nigh on impossible - which is why the immediate signal matters so much.

Time to change course

There is still time for the government to urgently reverse its decision to stop this chain reaction.

While I agree with the aim of raising mathematical and scientific attainment across the board - after all, the IB requires both - raising ambitions for more should not come at the cost of narrowing it for others.

In a labour market that rewards adaptability as much as technical skill, a settlement that sidelines the one route that guarantees breadth is hard to justify.

I do not envy ministers facing fiscal challenges. I know that in a less economically tight budgetary cycle, there would be no questioning the importance of retaining the IB for state school students. But we should also be honest about the scale of the cost.

Restoring the uplift would cost a few million pounds in a departmental budget approaching £100 billion. It would be trite to call it a rounding error, but we cannot pretend that it will have a serious impact on the department’s bottom line.

There is time to fix this. Our schools and colleges are asking the education secretary to reinstate the Large Programme Uplift without delay. Students and parents need certainty. School and college leaders also need to be able to set next year’s budgets, timetables and headcounts responsibly.

Ministers can fix this quickly by securing funding for IB schools and colleges.

A narrow system or a strong one?

This is not a choice between growing Stem ambition and the IB - it is a choice between a narrower system and a stronger one. Supporting the IB in the state sector keeps horizons open for students and shows that the government respects breadth and choice in the education system.

We must maintain access to this curriculum for schools that cannot independently afford the fees.

Otherwise this marks the reversal of a longtime precedent of equitable access to academic excellence with long-term impact on our students and our communities. That simply cannot be permitted.

Richard Markham is chief executive of the International Baccalaureate Schools and Colleges Association

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