Amanda Spielman has warned that she will not turn a "blind eye" to schools "narrowing the curriculum" as she launched her third annual report as Ofsted’s chief inspector this morning.
"We must not succumb to the seductive but wrong-headed logic that we are helping disadvantaged children by turning a blind eye to schools that are narrowing education if they deliver acceptable grades at the end," she said.
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Her comments are a clear rebuke to the leaders of two influential academy chains, who have 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," argued the chief executives of the Harris Federation and the Outwood Grange Academies Trust.
They added: "Nobody ever obtains a job or wins a university place because they have taken a virtuous curriculum."
Grades must reflect 'a proper education'
But this morning, Ms Spielman hit back, saying: "Grades are hollow if they don't reflect a proper education underneath."
She also warned: "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. And for those who aren’t being read a different story every night, who aren’t taken to the museum at the weekend, who don’t get the chemistry set for Christmas, it is especially impoverished.
"These children need and deserve a proper, substantial, broad education for as long as schools have them."
Since September of last year, Ofsted has been carrying out new school inspections that place greater emphasis on the curriculum and give less weight than before to exam results.
Ofsted has said this allows it to get to the substance of education. The new inspections are aimed at finding out whether a school's results are "the outcome of a broad, rich curriculum and real learning or of teaching to the test and exam cramming".
However, critics, which also include the Inspiration Trust MAT, have raised concerns that the inspections are penalising schools in disadvantaged areas that run three-year GCSEs.
The chief executives of Harris and Outwood Grange have described the new Ofsted set-up as a "middle-class framework for middle-class kids".
Primary science and 'stuck schools'
Today, Ms Spielman also raised concerns about science in primary schools.
The subject was removed from national curriculum tests taken at the end of primary school a decade ago.
This move may account for a slight fall in England's science results in the Programme for International Student Assessment (Pisa) tests, which are taken by 15-year-olds around the world, the report suggests.
The inspectorate said it understood why science had fallen down the priority list in many primaries, but that some schools were showing there was space in the curriculum to give children a good
grounding in maths and English while also building knowledge in other areas.
Ms Spielman is set to stress the importance of pupils having access to a broad curriculum as the new annual report is published.
The annual report looks at the performance of schools in 2018-19 and what Ofsted identifies as key issues in early years, schools, further education and children’s social care.
The school inspection reports analysed took place under Ofsted’s previous framework during the last academic year. But in recent weeks, there have been a series of major developments that could change the way Ofsted inspects schools.
The government has announced that it is to legislate to end the exemption that stops "outstanding" schools from being routinely inspected.
Under these plans, all "outstanding" schools will be inspected by 2025, with prioritisation of those schools that have gone longest without inspection.
During the general election campaign, the Conservatives also pledged to pilot no-notice inspections and to extend the length of school inspection of secondaries and primaries over three days.
And Ofsted announced last week that it wanted to trial a new form of deeper inspection into what it described as “stuck schools”, which have been rated as less than "good" over four inspections from 2006 to 2019.
It said the aim of these inspections would be not to pass judgement but to help these schools identify how to improve.
The watchdog has identified 415 “stuck schools”, which it says have been in a cycle of low performance despite receiving inspections and support designed to help them improve.
A Department for Education spokesperson said: “We worked closely with Ofsted on the new framework and the new school inspections are designed to check all pupils benefit from a broad and balanced curriculum while achieving good outcomes.
“Ofsted is clear that it does not have a preferred length of key stage 3 and schools will be judged on offering pupils an ambitious curriculum across their time in secondary school.”