Two flagship Norfolk academies which this week announced a big drop in GCSE results are being 'closely monitored' by the man given powers to intervene in under-performing academies.

Ormiston Victory Academy, in Costessey, this year suffered a 30pc point slump in the number of students gaining the key measure of five GCSEs at A*-C, including English and maths - from 73pc to 43pc.

Results at its sister school, Ormiston Venture Academy, in Gorleston, fell from 58pc to 43pc.

Both schools, which received multi-million pound re-builds after replacing their struggling predecessors, received Ofsted's top 'outstanding' rating in 2013.

A Department for Education spokesperson said: 'As regional schools commissioner, Tim Coulson continues to closely monitor both schools and work with the leadership to ensure all pupils get the excellent education they deserve.'

Regional schools commissioners were created earlier this year, and can intervene in struggling academies. Mr Coulson took up the post for North East London and East of England in July.

Ormiston Academies Trust, which sponsor both schools, has said it was 'not appropriate simply to compare this year's figures with previous years' figures', because of the changes introduced to league table criteria this year.

These included stripping out a number of non-GCSE qualifications which were previously counted as equivalent to one or more GCSEs, and only counting a pupil's first attempt at an exam.

It has also emerged that Norfolk County Council held discussions with Ormiston in September after they were told the schools' provisional results.

A spokesman for Norfolk County Council said: 'We are interested in the performance of all schools - including academies - and want them to do well for Norfolk children.

'In our role supporting and challenging schools, we have been working with Ormiston Academies Trust. This includes a discussion with Nicole McCartney - the national director of performance and partnerships at Ormiston Academies Trust - in September to discuss the academies' provisional results. We are meeting with the trust again next month now results have been verified.'

She added that the council was working with Mr Coulson to monitor progress at both schools, and had invited both academies to meet one of its education challenge partners, who review the performance of pupils and can discuss the improvement priorities for the year ahead.

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