Fresh concerns about the government’s vision of a schools system led by large academy chains have been raised by new major research, the leader of one of England’s biggest education providers and a senior Department for Education official.

They warn, independently of each other, that the sweeping changes to school organisation planned by the DfE could hamper results and lead to large chains of academies working in isolated “silos”.

The government’s ambition is for every state school to become an academy, with most operating within multi-academy trusts (MATs), which will be expected to grow to take in at least 10 schools.

But TES can reveal that an academic study, assessing the impact of MATs on pupil outcomes, shows that it is small MATs of two to three schools, rather than large chains, that have a positive impact.

Meanwhile, Roger Pope, the chair of the National College for Teaching and Leadership (NCTL) - an executive agency of the DfE - is fearful that many MATs will end up becoming “silos” that do not help any schools outside of their own chain.

And Steve Munby, a former NCTL chief now heading the Education Development Trust, which runs its own MAT, has expressed similar concerns that chains will work in isolation.

The new warnings follow Sir Michael Wilshaw’s condemnation of the vast majority of MATs as “mediocre” last week.

Now Toby Greany, a professor at the UCL Institute of Education, has revealed that his research suggests that the DfE strategy of encouraging MATs to take on more schools could be misguided.

“One of the findings is that it seems to be the small MATs - two- or three-school MATs - over a three-year period that are consistently making a positive impact on outcomes,” he said.

“The bigger trusts, not so. The bigger you get, the less clear that is.”

In evidence submitted to Parliament, the DfE says that MATs begin to enjoy their full benefits when they reach 10-15 schools.“Over time, we expect there to be many more MATs of this size, and we will therefore encourage and support MATs to grow,” the DFE says.

National schools commissioner Sir David Carter said MATs were “enabling schools to come together formally to drive up standards, share resources and staff expertise and, in many cases, act as sponsors and turn around the performance of schools that have been struggling for some time”.

This is an edited article from the 24 June edition of TES. Subscribers can read the full article here. This week’s TES magazine is available in all good newsagents. To download the digital edition, Android users can click here and iOS users can click here

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