Converting all schools into academies won’t make them all improve, but it is “unlikely to do them any harm”, a new analysis of government data finds.

The research also concludes that all-out academisation could close the gap between the very best and worst performing schools, as academy status tends to improve low performing schools but has little effect on high performing “converters”.

But the research author warns that plans to turn the remaining moderately performing schools into academies - as outlined in the recent education White Paper - could be expected to have a “marginal or non-existent” effect on their performance.

The report comes shortly after the three main classroom teaching unions, the NUT, NASUWT and ATL, all voted to oppose government plans for all-out academisation at their annual conferences this Easter.

The analysis on the SchoolDash education data website finds that the 792 high-performing schools that became “converter” academies in 2010 and 2011 did not significantly improve their GCSE results, relative to local authority schools with similar intakes, between 2012 and 2015.

In 2012, these converter academies had an average of 69.8 per cent of pupils achieving five good GCSEs including English and maths, compared with 67.9 per cent at similar local authority schools - a gap of 1.9 percentage points. By 2015, these converter academies were still only 2 percentage points ahead on this measure.

However, low performing schools which became sponsor-led academies in 2010-11 or 2011-12 did better at GCSE relative to similar local authority schools.

The analysis shows that these sponsor-led institutions saw a drop of 3.5 percentage points in the proportion of pupils gaining five good GCSEs including English and maths between 2012 and 2015, compared with a drop of 7.1 percentage points at similar local authority schools.

Narrowing the performance gap

Timo Hannay, the website’s founder and author of the blog posts, concludes that academy conversion does not necessarily help schools but it is unlikely to do them any harm.

He writes: “While [academy conversion] seems to have very little impact on the academic performance of successful secondary schools, it does seem to be an effective way to improve the performance of struggling ones.

“What does this say about the government’s desire that every school now convert to an academy?

 “If anyone tries to convince you that it will make all schools better then you shouldn’t believe them.

“But based on the evidence presented here - and obvious political frictions notwithstanding - it is also unlikely to do any of them much harm.

“The most likely positive effect is that it could help to close the gap between the best- and the worst-performing schools. But curiously, no one seems to be making that case.”

Speaking to TES, he adds that it is an “open question” as to what effect forced academy conversion would have on the remaining “moderately performing schools”.

“It might be expected to have a marginal or non-existent effect,” he says.

The Department for Education has been asked to comment.

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