A surprising 77% of schools rated as ‘Outstanding’ by Ofsted were downgraded after being re-inspected last year.

This means that fewer than one in four of the outstanding schools inspected by Ofsted retained their top grade.

The news comes after the Department for Education removed the bar that meant outstanding schools were not routinely inspected every year by the school inspectorate.

The report published today is the first since the organisation stepped up its inspection criteria and of the 117 schools that were previously exempt and were inspected between April and December 2018, one in three were rated as ‘inadequate’ or ‘requires improvement’.

27 outstanding schools retained their rating

The report highlights that only 27 outstanding schools retained their rating, 50 have been downgraded by inspectors to ‘Good’, 35 are at the ‘requires improvement’ grade and five were branded as ‘inadequate’, the lowest grade.

Ofsted lobbied for the exemption to be lifted and warned that many schools will have declined since they were last inspected.

The report also highlights that Ofsted’s warning was not without merit, but it leads to a problem for the government which has resisted calls so far for a change in the law.

Nick Gibb, the schools’ minister, said last December that Ofsted should review its risk assessment and arrangements to ensure it inspects 10% of the outstanding colleges and schools in 2019.

Previously, the school inspectorate would only have carried out an inspection if data highlighted a problem or if there was a tipoff over safeguarding issues.

Inspection exemption would remain in place

Mr Gibb said that the inspection exemption would remain in place and did not indicate whether Ofsted will be receiving more money to meet its targets.

The data also highlights that the proportion of schools who were inspected and then improved after receiving a ‘requires improvement’ judgement fell.

Ofsted says, in 2018, 58% of the ‘requires improvement’ schools did improve, which compares badly with 2016’s figure of 71%.

A spokeswoman for the Department for Education said: “The statistics show the standards in schools have risen since 2010 significantly.

“Ofsted inspects an outstanding school when specific concerns have been raised and while 65% of these re-inspected schools are outstanding or good, it’s to be expected that some schools will decline, which shows that the risk assessment approach works.”