From bitter debates over the pronunciation of “bath”, to weightier matters such as industry, politics and the proper way to play rugby, England’s North-South divide is long established.

But now it is being suggested that this fissure in the national fabric extends beyond economic history and cultural quirks into worrying new territory - school standards. The quality of education in the North, we are told, is lagging behind that in the South - in London in particular.

The last few months have seen both Ofsted’s chief inspector Sir Michael Wilshaw and education secretary Nicky Morgan warn of this geographical divide.

And their words are being heeded. A cross-party commission to look into the issue was launched last month by Nick Clegg - the latest big-hitter to speak out against a trend towards schools “underperforming” in certain areas of the country.

“We may live on a small island - but which corner of it our children call home makes a huge difference to their life chances,” the former deputy prime minister said.

A ‘national’ problem

The government’s anxiety about a North-South divide in education was spelt out in November, when journalists were told that Morgan was about to announce new measures aimed at “driving up standards in schools across the North of England, where historically performance has been poor”.

Later that day, the secretary of state duly said: “It’s a sad truth that when you look at many of the underperforming local authorities in our country, a significant proportion are located in the North of England.”

So ministers have made it clear that they believe that standards of school performance in the North are lagging behind the rest of the country. But the more you think about that idea, the more concerning it becomes. Schools policy is not devolved within England. We effectively have a national education service that recently has become more centralised than ever.

The influence of once-mighty local education authorities over schools has, in the past 30 years, almost completely vanished as greater school autonomy, mass academisation and the resulting funding cuts have successively taken their toll. Meanwhile, education ministers have paid lip service to school freedoms but have actually tightened their own grip on the classroom, issuing increasingly detailed diktats on what to teach and how to teach it. We have a national teacher training system, a national exams system and, until very recently, we had a national teacher pay system.

So if all schools in England are operating under these same conditions, how can there be so much difference between how good they are from one vast swathe of the country to another?

If there really is a North-South divide in school quality in England then something has gone badly wrong. But that, apparently, is exactly what Wilshaw believes. In December, he used the launch of Ofsted’s annual report to highlight the “alarming fact” that “educational success and failure aren’t spread evenly across the country”.

“Improvement in secondary schools has been driven by schools in the South of England,” he continued. “If you draw a line roughly from the Wash to the Bristol Channel, 79 per cent of the secondary schools below it will be good or outstanding compared with 68 per cent of those above it…We are witnessing an educational division of the country, with schools performing well overall in the South but struggling to improve in the North and the Midlands.”

Sir Michael continued the theme this morning with a warning that the government’s Northern Powerhouse would “splutter and die” unless secondary schools in Liverpool and Manchester improved.

“The facts are stark,” the chief inspector concluded in December.  But do they really stack up?

The two people with the most influence over how schools are run in England are telling us that those in one half of the country are underperforming when compared with the rest. How can that possibly have happened?

Has there been a secret plan to divide up the country’s teachers according to merit and send all the best ones down South? Is there a conspiracy among northern heads to run their schools into the ground? Or have Morgan and Wilshaw got it wrong?

‘Flawed’ theory

The theory of a strict educational North-South divide actually falls at the one of the first and most basic hurdles. Raw GCSE results, unadjusted for pupil background and compared by government office region, show that the North West actually does better than two regions situated further south - the East Midlands and West Midlands.

However, these statistics do reveal differences between average results in the nine regions, with London, the South East and the South West finishing top. The question is: do those differences tell us anything about regional variations in the quality of schools or are they a reflection of other factors - the most obvious one being pupils’ socio-economic background?

England’s old heavy industries were generally concentrated in the North and the Midlands. Their steep decline has left significant parts of these regions struggling to recover decades later. Aspiration and confidence have been stripped away in areas that have lost their economic reason for being. And depressingly, despite years of evolving school improvement policy, it is home background that still seems to be the key influence on how well pupils do in exams.

Compelling evidence - analysing GCSE results according to pupils’ home postcodes - has shown that even the “best” schools, with the highest results, struggle to get students from disadvantaged areas to do well.

So, is it really sensible to attribute largely geographical variations in exam results to the quality of education offered by schools in certain regions? It is not splitting hairs to point out the difference between relatively low exam results and poor schools; it is an essential distinction.

The latest published Programme for International Student Assessment (Pisa) results emphasise that point. They reveal that out of 66 participating countries and territories, the UK has the 16th highest level of variation between the test scores of individual pupils.

But crucially, 72 per cent of that variation in individual pupil performance occurs within schools, not between them - the 12th highest level in Pisa.

In other words, nearly three-quarters of the difference between pupil performance picked up by Pisa has nothing to do with the quality of whole schools. It could be down to differences in teachers. But the GCSE analysis suggests that it is just as likely to be caused by all schools’ failure to overcome disadvantaged pupils’ backgrounds.

Improving results for these pupils is obviously a pressing issue. But there is increasing evidence that low achievement is rooted in disadvantage at home. So, is it wise to subject schools with high concentrations of deprived pupils to another round of reforms and takeovers that are likely to result in more relative failure unless wider socio-economic problems are addressed?

That is exactly where ministerial and Ofsted claims of a North-South educational divide are taking us. Wilshaw used his December speech to call for an “education revolution” to tackle the unacceptable, “disproportionately sub-standard education” that “so many children in the North and Midlands” receive.

To be fair, the chief inspector’s conclusion is not based on a crude measure like GCSE grades, unadjusted for pupil background. But the increasingly strong link between test and exam results and the Ofsted judgments on schools that he cites means that it might as well have been.

Anyone doubting how closely raw results, and therefore pupil intake, are related to the watchdog’s verdicts need only consider the research showing that 76 per cent of selective grammar schools were judged “outstanding” in inspections up to January 2014. That compared with just 13 per cent of secondary moderns and 19 per cent of comprehensives.

So, if pupil intake can make such a stark difference to Ofsted outcomes, the 11 percentage-point gap between the proportion of secondaries judged “good” or “outstanding” in the South compared with the North and Midlands seems unsurprising. Given the difference in prosperity between the regions, it could be regarded as small.

High-achievers in the North

As far as actual GCSE results are concerned, any semblance of a coherent North-South, or rather North/Midlands-South divide disappears as soon as you look underneath the regional figures and examine results for individual education authorities.

Trafford, in Greater Manchester, is the second highest performing authority in the country. York, Cheshire East, North Tyneside, Wirral and North Yorkshire are other northern areas that make the top 30 of the table of 150 local authorities.

At the other end of the table, Milton Keynes, Lewisham, Plymouth, Portsmouth, Southampton, Peterborough and the Isle of Wight represent the South of England in the bottom 30.

The new cross-party Commission on Inequality in Education has avoided the trap of arguing that there is a North-South divide in school standards. But it has still made some pretty startling claims.

“It is not just the relative wealth of parents that holds large numbers of bright kids back: it is postcode inequality too,” said Clegg, the commission’s chairman, in a widely reported speech when he launched the inquiry this month.

Initial research for the commission, being organised by the Social Market Foundation (SMF), cites “big differences in GCSE results between worst-performing and best-performing areas”.

That turns out to be a look at the regional breakdown for 2014 in terms of the proportion of pupils achieving five A*-C GCSEs in any subject - which is actually no longer the government’s main measure. But the resulting seven percentage-point gap between London at the top on 70 per cent and Yorkshire at the bottom on 63 per cent, again takes no account of pupil background.

And Clegg’s claim that these differences mean that “what part of the country a child grows up in has a real impact on their life chances” seems to risk confusing correlation with causation. Indeed, Dr Becky Allen - one of the five commissioners recruited by the foundation to carry out the inquiry - tells TES: “Regions are far too large and diverse to make generalisations about whether school standards are high enough.”

Allen, director of Education Datalab, has produced her own analysis of GCSE results from 2015, which reveals just how much the regional rankings can change depending on the measure used. Her starting point was a look at the average GCSE grade.

Both raw results - as well as a value-added measure that looks at the progress achieved from key stage 2 tests - put London at the top, the South East in the top three and the North East at eighth in the table of nine regions.

But when contextual value-added is calculated to take into account pupil background, the South East drops down to eighth place and the North East shoots to the top of the table, pushing London into second place.

Allen conducted a similar exercise with primary KS2 test results from 2015, which shows little regional difference in terms of raw results - and, she notes, “no signs of a North-South divide”.

When value added is introduced, London and the North East are the clear top primary performers, in first and second position respectively. And when contextual value added is applied they swap places, with the North East coming top again.

The apparent success of both primary and secondary schools in the North East - once pupil background is taken into account - is particularly noteworthy, as Wilshaw singled the area out as illustrating the problem of a secondary North-South divide “better than any other region”.

Contextual value-added figures do come with a health warning, though. Another respected education academic, Professor Stephen Gorard, has argued that they are error-ridden and therefore “useless” for comparisons. Nevertheless, Allen’s results are, as she puts it, “interesting”.

The SMF did try to dig a little deeper with a comparison of two sets of verbal reasoning tests taken by 11-year-olds born in 1970 and in 2000. Researchers broke them down by children’s region, ethnicity and parental income, and conducted a regression analysis to isolate the impact of the three separate variables.

It did find regional differences in the 2000 cohort, even after pupil ethnicity and parental income were accounted for. Children in the North West did better than those in London and those in the capital outperformed pupils in Yorkshire and in the West Midlands. But the impact of parental income remained greater than geography.

The poverty factor

And Gorard casts doubt on the entire analysis. The Durham University academic says that the foundation was right to draw attention to regional differences in school outcomes. But he warns: “They are wrong to attribute [regional differences in results] to the impact of location rather than pupil background.”

Poverty is greater, on average, in the North and the Midlands, Gorard says. However, he adds: “This is not being picked up by the relatively small number[s] - with high levels of missing data - in the two birth cohorts cited.”

But if the foundation’s results are correct, they appear a strange finding for a national schools system. If social background has been accounted for, why on earth should Yorkshire pupils do worse than those elsewhere? A colder climate? The damaging effect of Yorkshire puddings?

The elephant in the room here, of course, is London, which has seen a remarkable turnaround in its schools’ results. Between 2003 and 2011, the capital moved from being the worst GCSE performer of England’s nine regions to the best, and it has stayed there.

London boroughs make up six of the top 10 local authority performers at GCSE level and even comparatively deprived boroughs like Tower Hamlets, Hounslow and Southwark make the top 20. Everything from a booming economy to a supply of bright young teachers and the success of the London Challenge initiative have been suggested as reasons for the capital’s success.

Generous per-pupil school funding may also help; the 17 authorities best funded for education in England are all in London.

But research from Professor Simon Burgess has suggested that, once again, it is pupil characteristics that are key, not what schools do. According to the Bristol University academic, the single, simple reason for London’s relative success at GCSE is its high proportion of ethnic-minority pupils. And he says that exam results in Birmingham have been boosted in the same way.

When this explanation was put to Clegg last month, the former deputy prime minister questioned why “Manchester, Sheffield and Leeds, for instance” had not also had results boosted by similar communities (although Burgess points out that they are “less diverse than London”). That, presumably, will be one of the questions that the commission will examine.

In the meantime, ministers have already decided what the problem is and how to solve it. The education side of the government’s “Northern Powerhouse” initiative will see a £10 million pot going to existing academy sponsors to create and run at least 12 local “academy hubs” in “challenging and disadvantaged” areas.

‘Misplaced focus’

Allen argues that the government’s whole northern focus is misplaced. “This is a rather simplistic narrative on schools,” she tells TES. “There are certainly localised areas where the schooling system needs greater support… located in all parts of the country.”

But Hamid Patel, chief executive of Tauheedul Education Trust - a sponsor that will run new academy hubs in Bradford and Greater Manchester - believes that they will help to create previously lacking school improvement capacity in the North and redress an old imbalance. “Government [education] investment historically has been higher in the capital, closer to the seat of government,” he notes.

Sir Michael Wilkins is chief executive of the Outwood Grange Academies Trust, a Wakefield-based sponsor that will use some of the money to expand academy hubs in Teesside and South Yorkshire. He is confident of success, but he warns: “To lead a school is tough in any position, but when you are taking a school in a very deprived community that has had years of underpeformance then there are lots of factors you have to overcome. It can be very difficult to shift aspiration levels.”

The fact that all the hubs will be expected to take on “underperforming academies”, as well as maintained schools, is testament to how central government education policy in these areas has previously failed to overcome wider socio-economic problems.

Yet, once again, the narrative is building that this is the fault of “underperforming” schools. As the statements from one big political hitter build on those of another, it is rapidly becoming an established “fact” that the geographical area in which you live makes a significant difference to the quality of state-school education that you will receive.

It is a strange claim that is based on the most tenuous of evidence. Yet as it gets taken up by increasing numbers of well-meaning and influential policymakers, the danger is that it could obscure the real problems faced by our schools and the wider solutions that they need.

A Department for Education spokesperson said: “The landscape of English education has been transformed over the past five years through raising both standards and expectations. Thanks to the hard work of teachers across the country and our ambitious programme of reforms, there are now 1.4 million more pupils being taught in good or outstanding schools since 2010 - including 610,000 more pupils in good or outstanding schools in the North.

“This progress should not be ignored, but like Sir Michael Wilshaw we believe too many young people aren’t being given a chance to fulfil their potential because of where they live, so we want to work with the sector to tackle those pockets of underperformance, and extend opportunity to every single child.

“We are giving more power and responsibility to teachers through the academies programme, we are introducing new measures to transform failing and coasting schools, funding the best academy chains to share excellence in struggling regions in the North and creating a National Teaching Service - sending some of our best teachers to the areas that need them most.”

William Stewart tweets as @wstewarttes

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