School inspectors are observing too few lessons and relying too heavily on heads and teachers to evaluate their own performance, MPs will say today.

A report from the Commons Education Select Committee also says that light-touch inspections by Ofsted may not be picking up on previously good schools that are now coasting.

The committee suggested that Ofsted was being too hard on other schools by stating in its annual report that those judged to be “satisfactory” were not good enough. Discussion on school performance should be constructive, not accusatory, the MPs say.

Ofsted changed the way it inspected schools in 2005. Under its new “light touch” regime, schools are inspected more often, with less warning, and inspections take a couple of days rather than a week. Reports are also shorter. A survey of schools found that the majority (88 per cent) were satisfied with the new regime. But the committee identifies a number of serious flaws in the new process.

It questioned whether schools’ self-evaluation reports, which now form an important part of the inspection regime, provided an accurate picture of the quality of teaching within a school. “We urge Ofsted to ensure that self-evaluations are of sufficient quality and accuracy,” it says.

Under the new system, the highest performing schools undergo very short “reduced tariff” inspections. But the MPs say it is not clear what qualifies a school as “high-performing” in the first place. They add that inspectors may not have enough time to pick up on falling standards.

Barry Sheerman, the committee’s chairman, said yesterday that the new inspection service concentrated on assessing quality, not on helping schools to improve. “It still appears that Ofsted has no capacity to give advice when a cluster of local schools suffers from systemic underperformance. This continues to be a weakness in the system,” he said.

The report cautions against inspectors relying too heavily on statistical judgments about how good a school’s test and exam results are, rather than the quality of teaching.

The MPs also question Ofsted’s ability to cope with its new extended role from April this year, when it merged with other inspectorates including the Adult Learning Inspectorate and Children and Family Court Advisory Service. “We cannot disguise our concern as to the fitness for purpose of the organisation,” the MPs say.

Mary Bousted, general secretary of the Association of Teachers and Lecturers, said she shared the select committee’s concern that light-touch inspections were not fit for purpose in some cases. “The wrangling over the definition of a ‘satisfactory’ school shows clearly that Ofsted is unable to provide the kind of clear information needed and wanted by parents and pupils,” she said.

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