Top headteachers say they are being “penalised” by Ofsted for doing what the government wants and helping to turn around struggling schools.

Chief inspector Sir Michael Wilshaw and Prime Minister David Cameron have called on the best school leaders to improve more than one school and share their expertise where it is needed most.

But Ofsted’s official policy is not to take this work into account when grading the quality of leadership during school inspections. Now angry headteachers say they are being unfairly treated for doing the government’s bidding, and warn that the policy could deter others from offering extra support.

Clive Mathew, headteacher of John Henry Newman Catholic School in Stevenage, has worked with his leadership team to secure improvements in his own school and pull another secondary out of special measures within in a year.

But despite this “crippling” effort, his school’s leadership grade dropped in its last Ofsted report. “Why would anybody work with another school?” he said.

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