Class photos haven’t changed much. The top row stands, the middle row sits and the front row lines up cross-legged on the floor, just as children have done since Victoria was queen. There’s always someone scowling mutinously, someone beaming and someone with a rictus grin who looks like they’re seconds away from bursting into tears.

Class photos are touching and endearing; they also make childhood appear unchanging from one decade to the next.

But nothing could be further from the truth.

To any Scottish primary school teacher surveying their class photo in 2023, they see not uniformity, but a quite staggering spectrum of need. Perhaps a boy at the back is on the autistic spectrum and a girl at the front too. Three children might be awaiting a dyslexia assessment and one might have attention deficit hyperactivity disorder. Two further children could be wrestling with anxiety and one might have suspected foetal alcohol syndrome. A couple of others could have delayed speech and language.

This scenario might sound far-fetched, but it is in fact just average. Figures published by the Scottish Government this week reveal that the number of children with additional support needs (ASN) has reached a record high of 259,036, or 36.7 per cent of pupils. The numbers have doubled in a decade, partly because of better identification and recording of needs, and partly it seems because of the stress, isolation and disruption of the pandemic and cost-of-living crisis, resulting in more children with social, emotional and behavioural problems. ASN is not on the margins any more – it’s very much the mainstream.

But in tandem with this precipitous rise, the numbers of specialist teachers and other staff to support these children has been falling. Councils have a responsibility to meet children’s needs, but the picture is if anything getting worse. The number of ASN teachers in Scottish schools fell by 681 between 2010 and 2022. Too often, when budgets are tight, ASN teachers and resources are squeezed. It’s not just specialist teachers that are in short supply, but other support staff like educational psychologists and children’s mental health professionals. Teachers report that rising levels of school violence are linked to children’s additional support needs not being met.

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This is fast becoming the most pressing issue in school education.

Go into schools and you won’t find any lack of will to support children with ASN. There are many humbling examples of inspiring, energetic headteachers and staff doing the best they can by these children. Innovations like nurturing wellbeing hubs in secondary schools show what can be done within the existing budget.

But a review of how well councils’ statutory ASN responsibilities were being delivered, published in 2020, noted that it was “overdependent on committed individuals” and “fragmented and inconsistent”. In a letter to this newspaper recently, the independent chair of that review, Angela Morgan, wrote: “The question is not how we make a third of our children fit in with mainstream education, the question is how we change mainstream education to fit the reality of all children’s lives in Scotland.”

This issue impacts on everything that matters in education, including standards, behaviour and the attainment gap. Children from poorer backgrounds are disproportionately represented in the ASN statistics, and children with ASN are less likely to achieve expected standards of literacy and numeracy. The Scottish Children’s Services Coalition (SCSC), an alliance of bodies providing specialist education to vulnerable children, which campaigns tirelessly on this issue, recently said it would be “extremely challenging” to reduce the attainment gap for children with ASN in current circumstances.

One expert on children with ASN I spoke to for this column says he feels bleak about the future, warning that supporting children with ASN is “preventative” and that if they aren’t getting the support they need in childhood, it will create problems that are “twice as big” in 10 years’ time as some of these children struggle in the adult world, for instance with mental health and employment.

Scotland already spends more per pupil on education than other UK nations, but either the money isn’t being spent as effectively as it could be or more is needed.

Right now, we don’t even have a clear path to improvement. At Holyrood on Tuesday, education secretary Jenny Gilruth gave a thoughtful statement on the state of Scottish education, with a frank acknowledgment of shortcomings and no glib solutions offered.

But she had little to say on ASN until pressed by opposition MSPs. What was being done to remedy the shortfall of ASN teachers? asked Liam Kerr for the Scottish Tories.

There is a “real lack of detail” from the minister on pupils with ASN, added Pam Duncan-Glancy for Labour. Were the minister’s actions going to meet the scale of the challenge?

It was fairly obvious to any observer that the answer was no. Ms Gilruth noted that the number of learning support assistants was at a record high, which certainly matters since these staff provide vital help, support and friendship to children with ASN, but it’s not a solution in itself. Specialist teachers are needed, for instance, to carry out dyslexia assessments, which many children around Scotland are waiting years for.

Ms Gilruth did at least acknowledge the problem and make a promise of sorts to address it, saying: “We need to look again at how we can resource that need”. She pledged to work with councils to prevent regional variation in support for kids with ASN and sounded frustrated that some councils hadn’t used a special ring-fenced fund of cash to protect teacher numbers. She even threatened to withhold funding from councils that weren’t spending the money as intended.

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Fair enough, but this can’t be allowed to descend into a blame game between ministers and local authorities. Both know that teachers are under huge pressure and it’s up to them, together, to sort it out. Teachers and parents will be looking at next week’s Scottish budget with great interest: will there be more money to boost support for children with ASN? Or is this sorry situation to drag on?