One of the country's largest and most influential academy chains has strongly rejected Ofsted's apparent suggestion that it is achieving "success without substance".
The Harris Federation hit back this morning after Ofsted's chief inspector, Amanda Spielman, used the launch of her third annual report to warn against schools "narrowing education" in order to deliver "acceptable" GCSE grades.
Her comments follow academy chains' complaints about Ofsted criticising the use of three-year GCSE courses.
But Ms Spielman said today: "Grades are hollow if they don't reflect a proper education underneath."
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She also said: "We must guard against restricting education excessively. Exam results are important but have to reflect real achievement.
"We should not incentivise apparent success without substance. This doesn’t represent a good education for any child."
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This morning Harris chief executive Sir Dan Moynihan countered, saying: “Aside from our EBacc entry and pass rates, which are far higher than the national average, our students are passing other subjects, including drama and music, at a rate of almost twice the national average and attending the best universities in the UK and worldwide.
"This is not an example of ‘success without substance’; it is an example of disadvantaged children breaking the class ceiling.
“The consequence of stopping us, and other schools like ours, from giving our students a three-year run at their GCSEs is that we will see schools in middle-class areas excel and schools in other places fall behind.”
Ms Spielman's comments this morning were a clear response to Harris and Outwood Grange Academies Trust, which had complained about Ofsted's new school inspection framework and its crackdown on three-year GCSE courses.
"The reality is that children from tough backgrounds need the credentials that exam grades give to help them get on in life," the Harris and Outwood Grange chiefs argued.