It’s like buses: you wait ages for one then three come along at once. So it is with perhaps the most contested issue in education - the question of whether academisation raises school standards.

Within the past two weeks, three reports have sought to address this issue. The Sutton Trust’s ”Chain Effects 2016” analysed the impact of academy chains on low-income students. The Education Policy Institute’s (EPI) research report looked at school performance in multi-academy trusts (MATs) and local authorities, and the Department for Education’s (DfE) statistical working paper reported on MAT performance measures.

Rather remarkably, the three reports came to broadly similar conclusions:

• The DfE’s analysis shows that 50 per cent of MATs are currently performing below or significantly below the national average for value added at key stage 2, something which certainly should give the government cause for concern. It is even more worrying, however, that the DfE’s own research shows that 54 per cent of MATs are performing significantly below the national average for value added at key stage 4, which is, in anyone’s terms, something of a shocker;
• The Sutton Trust research reveals that the academies it analysed (all of which have been sponsored academies for at least three years) are twice as likely as mainstream schools to be below the floor standard and twice as likely to be judged inadequate by Ofsted; 
• The EPI research shows that, at secondary level, nine of the worst schools groups are MATs, which means that MATs make up a disproportionate number of the lowest-performing groups.

Just in case I could be accused of misrepresentation, let me add some better news:

• Seven of the 39 chains analysed in the Sutton Trust report perform significantly above the national average for all mainstream schools (maintained and academies) for their disadvantaged pupils, and about half are improving faster than the national average. However, 13 MATs are attaining significantly below the national average and of particular concern are the eight chains in which both attainment and improvement were below the mainstream average.
• At primary level, according to the EPI research, MATs are slightly over-represented in the top-performing group but are also slightly over-represented amongst the lowest performers.

The overriding conclusion of both the Sutton Trust and EPI reports is that there is wide variation in MAT performance. According to the Sutton Trust’s analysis “the main picture is one of a lack of transformative change”. The report concludes that the government “needs to act radically and rapidly to ensure that the promise of the policy programme is realised in improving the educational experiences and outcomes for disadvantaged children. Otherwise there is a real danger that the programme becomes part of the problem rather than part of the solution’.

These are strong words, and they are matched by the conclusion of the EPI report: “The analysis we have produced casts doubt on the government’s previous policy of academising all schools. It is not clear what the gains from this would be in terms of school performance, not least for schools in high-performing local authorities.”

Given the weight of evidence, it is difficult to see how government ministers can continue with their mantra that academisation raises school standards. So I was not surprised, listening to a speech by Lord Nash, the minister in charge of the academies programme, that the government has subtly shifted ground in its intention that all schools must become academies.

Lord Nash reiterated the government’s view that MATs are the best vehicle for school improvement, saying that on a scale of one to 10, MATs are currently at level three. There is, he argued, much more capacity for MATs to improve once the academisation programme has taken root. Lord Nash was clear, also, that MATs are the way to get better teaching standards, more effective CPD and widening career opportunities for teachers and school leaders as economies of scale enable MATs to commission back office services, foster school-to-school collaboration and develop CPD.

‘Good teaching and good leadership are the solution’

Now, I like a good story as much as anyone, but I had difficulty believing this one. There are just too many impossible things to believe before breakfast in Lord Nash’s golden MAT vision. Since when, for example, has current poor performance been excused by the prospect of improvement some years down the track? Remember the avowal by Nicky Morgan, the newly departed secretary of state, that children in poorly performing local authority schools should not have their education harmed for a single day? Or is this now only the case for local authority schools, while children in under-performing MATs simply have to accept that they are part of a large experiment which may turn out OK for their successors sometime in the future?

Lord Nash was clear, also, about the context in which high-performing MATs operate. They are large enough (around 10 to 15 schools) to generate economies of scale, geographically not too far from each other, and focused on constant improvement. But the majority of MATs are made up of much smaller numbers of schools - typically one to three. And many converter academies stand alone. They cannot generate sufficient economies of scale, nor can they benefit from school-to-school collaboration, in the same way larger MATs do.

In the case of MATs, size does matter. While many MATs are too small, others have become far too big, far too quickly. Going for growth, they have become too geographically dispersed and lack the resources and connections to support their schools and to share good practice.

The authors of both the Sutton Trust and EPI reports make some strong, and consistent, recommendations. These include:

• The government, national schools commissioner and regional schools commissioners must act urgently to create mechanisms to ensure the spread of good practice from the best academy chains to the rest; (Sutton Trust)
• The government could either allow high-performing local authorities to become academy trusts, or it could avoid forced academisation of high-performing local authorities. (EPI)

There are many other challenging conclusions and recommendations in both these reports, the summaries of which are well worth a read. But one thing is clear. Academisation casts no fairy magic dust on schools and does not improve school performance.

If the government carries on focusing on mass academisation it will continue to miss the central and crucial point that it is good teaching and good leadership which enables schools to improve, not whether they are run by a MAT or a local authority.

Dr Mary Bousted is general secretary of the ATL teaching union. She tweets as @MaryBoustedATL

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