A headteachers’ union has dealt a major blow to Ofsted today by warning that the inspectorate cannot reliably judge the quality of education at a school through new inspections focused on the curriculum.

The NAHT heads’ union has told Ofsted that it disagrees with its plan to create a new quality of education judgement, which would take into account teaching and learning, curriculum and exam results.

This proposed change to school inspection, which would promote the importance of the school curriculum, is at the heart of Ofsted’s plan for its new framework - which is set to be launched in September.

Quick read: Heads voice fears over new inspections

Need to know: Ofsted’s new framework

Analysis: ’Inspection changes fall short’

Ofsted wants to replace both the teaching and learning and the pupil outcomes categories within inspection reports with a new quality of education judgement, which would look at the intent, implementation and impact of a school’s curriculum.

Ofsted ‘looking at too much content’

However, the NAHT’s general secretary, Paul Whiteman (pictured), said today that the proposal will not work because Ofsted is looking at too much content to be able to form a single judgement on the quality of education in schools.

Tes can also reveal that an NAHT poll of its members found that the vast majority are opposed to Ofsted’s plans to extend the inspection of “good” schools from one day to two and the plan for a lead inspector to arrive at a morning’s notice to begin on-site preparation for inspection starting the next day.

However, the majority of members support Ofsted’s plan to separate pupils’ personal development and behaviour into two inspection judgements.

Under Ofsted’s plan, schools would still get an overall judgement of either “outstanding”, “good”, “requires improvement” or “inadequate”.

In the NAHT response to the consultation, seen by Tes, Mr Whiteman said: “The NAHT believes that the quality of education judgement is too complex and dense to be applied with consistency across the inspection workforce. This is a particular concern given the irregular deployment of most Ofsted inspectors, and the continuing high turnover of HMI.”

The NAHT also warns that Ofsted’s draft inspection handbook has not addressed concerns about reliability and consistency in inspectors’ judgements.

It suggests that the new plans could bring in more subjectivity to inspectors’ judgements.

Mr Whiteman added: “The quality of education judgement effectively incorporates existing judgements on outcomes for pupils and the quality of teaching, learning and assessment, overlaying these with a tripartite approach to the evaluation of the curriculum. In NAHT’s view, there is simply too much content to be evaluated within a single judgement.”

The NAHT’s comments come as a report published today by the EDSK thinktank suggests that Ofsted inspection judgements should be scrapped because it has not been demonstrated that they are reliable.

The NAHT response to the Ofsted consultation on the new inspection framework reveals:

• 91 per cent of heads polled disagreed with plans for inspectors to arrive at a morning’s notice to begin on-site preparation the day before inspection;
• 88 per cent of heads oppose extending short inspection of “good” schools to two days;
• 86 per cent of heads oppose Ofsted’s plan to no longer look at internal school data;
• 63 per cent of heads agree with Ofsted separating personal development and behaviour into separate categories.
   

On the plan to extend inspection of good schools to two days, the NAHT response says: “NAHT is strongly opposed to this proposal. Increasing the burden of inspection on ‘good’ and ‘outstanding’ schools is a step in the wrong direction. This proposal undermines the original intention of short inspection, which NAHT supported, as a light touch health check.”

Last year the NAHT led an accountability commission, which said that Ofsted inspections should be focused on schools that needed support to improve.

An Ofsted spokesperson said it was not commenting on individual submissions to its consultation.

She added: “We will be taking all responses into account and will publish our full response to the consultation in May.”