Standards at Norfolk schools are causing 'considerable concern' for inspectors who warn too many pupils do not have access to a good education and the county council is failing to step in early enough.

A blitz of school inspections, which saw 28 primaries and secondaries visited over just one week, found three out of every five schools assessed were not providing a good enough education to youngsters.

Raising 'considerable concern' over its findings, Ofsted said it was particularly worried by the lack of progress made at more than 10 schools judged to require improvement and the decline seen at a further six schools which have now been found to require special measures.

It accused the county council of failing to step in quickly enough when schools were known to be struggling. In a critical letter sent to Norfolk's director of children's services, Lisa Christensen, Ofsted's regional director Sean Harford said: 'This will be worrying to parents and carers, and means the pupils in these schools don't have access to a good quality of education.'

Last night, Norfolk's schools said they were working hard to address any problems raised as a result of the focused inspections.

And while admitting Norfolk's below-average performance was not good enough, the county council stressed the overall findings were not representative of the current picture in Norfolk, where 66pc of schools were now good or outstanding.

Gordon Boyd, assistant director of children's services, accepted Ofsted's findings and said none of the outcomes came as a surprise. He stressed schools were responsible for their own improvement, but the council was committed to playing its part as 'champion of Norfolk's young people'.

Just one of the 28 schools visited as part of the focused inspections in March earned an outstanding grade – St Martin's at Shouldham Primary – while 36pc were rated good. Seven had improved from satisfactory while the Short Stay School For Norfolk was inspected for the first time.

Viewed together, the reports paint a worrying picture of education in Norfolk and put pressure on headteachers and governors to make improvements.

Problems raised ranged from poor results and inadequate progress by pupils to ineffective governing bodies and overly-optimistic school leaders.

Among those rated inadequate and placed in special measures was Cavell Primary in Norwich. Headteacher Simon Wakeman said he was disappointed that Ofsted had not recognised the school was on track to achieve its best-ever results this year but added: 'We have already put in place an improvement plan with the full support of the local authority, who are working very closely to support and challenge us through this process. We are confident that when they next visit, they will see the improvement plan already yielding results.'

But that county council support and challenge experience is too often lacking, according to Ofsted.

During its week of focused inspections, the watchdog also took stock of what schools and their governors thought about the local authority's role.

Based on surveys carried out at each of the 28 schools, as well as phone calls with a further 21 good or outstanding schools, inspectors said they often felt they were not challenged enough.

In its letter, Ofsted said: 'Support provided by the local authority for those schools found to require special measures has not been effective. Known weaknesses and barriers to progress were not tackled soon enough. Local authority officers have been too accepting of the school's self-evaluation and reached an over-generous view of performance.'

Norfolk County Council said its A Good School For Every Norfolk Learner initiative, approved earlier this year, would go a long way to address the concerns raised by Ofsted. Ms Christensen said: 'Among other things, this strategy will see us being a firmer, critical friend of schools and their education improvement wherever necessary.'

A £1m investment will help to link schools deemed to require improvement with good and outstanding schools and encourage them to learn and a 'top headteacher' will soon be announced to lead it.

Mr Boyd said the authority was also set to make greater use of its powers to intervene. Already, the governing body at Moorlands Primary School has been removed and replaced by an interim executive board following an inadequate inspection last October.

'We are doing that in two or three schools,' said Mr Boyd, who also said more warning notices would be issued.

Last night, North Norfolk MP Norman Lamb, pictured left, said addressing problems at the county's schools had to take 'absolute priority' adding: 'We have to be prepared to act where a school is failing or is weak because children only get one chance.'

Elizabeth Truss, MP for South West Norfolk and education minister, said the findings were 'very disappointing' and added: 'I will be seeking assurances that measures are being implemented, as a matter of priority, to rectify this situation.'

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