Parents will be able to instigate an Ofsted inspection of their child’s school if they feel that teachers are coasting or failing to stretch pupils to their full potential, under an important reform of the school inspection system.

The proposals will be outlined today by Christine Gilbert, the Chief Inspector of Schools, as part of plans that could mean the weakest schools facing annual visits from the Ofsted inspectorate and the best schools inspected only once every six years.

Currently, schools are inspected every three years. Ms Gilbert wants to change this so that more attention is focused on the weaker performers and less on the strongest.

In order to ensure that good schools do not lose momentum in the longer period between inspections, Ms Gilbert wants a mechanism that will enable parents to alert Ofsted – either directly or through the governors or local councils – if they believe that standards are slipping. The proposals are part of a wider drive to involve parents more directly with school inspections. At present parents are given only one or two days’ notice that their school is to be inspected. Many complain that this does not give them sufficient time to inform inspectors of any concerns. Parents’ views are rarely mentioned in inspection reports.

Last year Ofsted received new powers to investigate complaints about schools by parents. But Ms Gilbert has been frustrated both that relatively few parents have taken advantage of them and that the remit for complaints that inspectors are allowed to accept is too restrictive. Ofsted’s last annual report says that inspectors received only 52 complaints that were within its remit from the parents of the 7.3 million children at state school in England last year. Only 38 complaints were retained on school files for inspectors to see at their next inspection.

Ms Gilbert also wants a system of three-yearly “health checks” between six-yearly inspections. These will involve inspectors checking school data and looking at parents’ views. They will then produce a very short report.

For these purposes she will put in place a separate mechanism to “collect the views of parents at regular intervals and use that at regular intervals at the health check for the school”.

It is likely that there will be some means for parents to contact inspectors online.

In comments before today’s announcement she said: “One of the things our board were concerned about was that children might go through school for six years not having an inspection at all, so we think we need some sort of check . . .

“If there is a pattern of lack of satisfaction from parents over a period of time that is something we should talk about and think about and consider whether an inspection is therefore needed.”

Ms Gilbert is convinced that parents would welcome more opportunities to bring their concerns to the attention of Ofsted. “Parents are positive about inspection. MORI last year identified only 4 per cent of parents not in favour. They are not worried, I think, about the form of inspection, they just want to know that something is being done,” she has said.

She is equally aware, however, of the need to safeguard against vexatious or malicious complaints from parents and will be consulting widely about how to minimise this risk.

Today’s consultation document will also contain plans to increase the hours that Ofsted spends observing lessons during inspections, in response the criticisms that new “light touch” inspections were too superficial.

Classes at high performing primary schools are observed for an average of three hours per inspection over one or two days, although in some cases it can be a little as an hour. This will now increase “significantly”.

Under the old system, in operation until 2005, all schools faced about 24 hours of lesson observation, spread across one or two weeks.

Margaret Morrissey, of the National Confederation of Parent Teacher Associations, said that she was sceptical about the idea of allowing parents to trigger Ofsted intervention.

“You get into dangerous territory where a school is living in fear of its parents. Parents should have a role, but the majority of them are not trained to do this.

“The only way I would be comfortable with this is if the parents had first to report their concerns to the local authority and then the local authority takes it up with Ofsted,” she said.

Chris Keates, general secretary of the NASUWT teaching union, said she was concerned about Ofsted holding parents’ complaints about schools and individual teachers on file without the head teacher’s knowledge — even where complaints were anonymous.

“It is like saying to schools, ‘We don’t trust you, so we are going to have the parents tell tales on you’,” she said.

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