Colin Richards, a former HMI and a primary sector specialist adviser to Ofsted, writes:

Now that the dust is beginning to settle, all of us need to learn lessons from the “Trojan Horse” affair, not least Ofsted itself. In his public comments on Ofsted’s findings, the chief inspector, Sir Michael Wilshaw, castigated almost all parties involved including governing bodies, the local education authority, the Education Funding Agency and, indirectly, the Department for Education. Of the official bodies involved with Birmingham schools, only Ofsted itself escaped from Ofsted criticism. Plus ca change?

I am not concerned here to critique the actual findings of the Ofsted inquiry; I have no inside knowledge that would lead me to support or reject the recommendations. I do, however, have considerable reservations about Ofsted’s unwillingness to acknowledge the limitations of its own procedures and processes that have contributed to the current crisis. I focus on two of these here.

First, in its section 5 inspections Ofsted focuses on pupils’ achievement, teaching quality, leadership and management, and pupils’ behaviour and safety. All but the latter are referenced in relation to Ofsted’s current preoccupation with reporting achievement expressed in terms of performance data.

Conspicuous by its absence as an explicit focus is the quality of the school’s curriculum, its main medium for the transmission of knowledge, understanding and values. Yet it is the last of these that is at the heart of the current Trojan Horse controversy.

In his comments, the chief inspector does not acknowledge that curriculum lacuna in the very heart of its normal processes of school inspection. Tinkering with the current criteria and guidance, as is being suggested, will not do. The curriculum needs detailed explicit attention in any worthwhile inspection.

A second lesson Ofsted should draw is the inadequacy and deleterious effect of its four-fold categorisation of schools (“outstanding”, “good”, “requires improvement” and “inadequate”). To reduce the complexity of a single school to a single descriptor is gross injustice and to allow that descriptor such public currency adds to that injustice - compounded when a school appears to plunge from “outstanding” to “inadequate” in a short period of time.

Every school is a complex amalgam of strengths and weaknesses and it is these that need to be communicated to those who need to know. Single descriptors get in the way of sophisticated professional analyses and detract from forensic examination of what is working well and not so well in relation to any school’s declared aims and values.

Just as Ofsted has moved away from offering lesson grades, so it should move away from offering crude overall grades in its school inspection reports. What is needed instead are bespoke reports which, in a readable way, provide an independent professional evaluation of the values, aspirations, achievements and shortcomings of particular schools as a basis for dialogue with parties interested in the educational well-being of their learners. Forcing crude overall gradings on schools stifles rather than stimulates that sophisticated dialogue.

I hope that the chief inspector will learn lessons from the Trojan Horse inquiry - including acknowledgment of Ofsted’s own limitations - and that he won’t allow aspects of the “old” Ofsted mindset to derail the much-needed rehabilitation of school inspection in England.