It’s time for Ofsted to be inspected. It’s time that the inspectorate itself felt the cool hand of inspection on its shoulder.

It has become far too important and far too influential: I’m sure this was not the original intention. Rather than being merely an accountability body for education, it almost controls the direction of education itself in this country - and that should not be its remit.

Over the course of the quango’s existence, it has ruined more teachers’ lives and schools than we can mention and it has treated many more with utter contempt.

Having experienced eight inspections in most of its iterations, I feel qualified to comment on the evolving role of the inspectorate and its power over schools.

For example, I will always remember the day one of my brilliant Year 6 teachers undermined the validity of the system. During the course of the inspection, he demonstrated its flaws when he pointed out that he’d taught the same lesson for his past three inspections and it had been graded differently each time.

Ofsted is failing our education system - one of the main reasons is that many inspectors are not up to the job being asked of them. Too few have been a heads or heads of department, and they lack both the experience and intuition to gauge the quality of a school in the limited time they have within it.

Ofsted has produced ‘robot schools’

Responsibility for our shrinking curriculum and preoccupation with data must also, at least in part, lie at the door of Ofsted. Its chief inspector went some way to admitting it yesterday. Ofsted has produced robot schools, all mindlessly doing the same things and truly scared of being different in their approach to the curriculum.

Ultimately, the recruitment, retention and workload crises are also, largely, the responsibility of Ofsted, too. Schools in tough socioeconomic areas haven’t a chance when Ofsted wields it axe, and nearly all schools are driven to make greater and greater demands on their staff as they try to second-guess what inspectors are going to want.

We can and must do accountability better. Let’s start by scrapping school grades and recognising that all schools want to improve continually.

Ultimately, however, I believe that Ofsted has had its day. So how would I inspect it? And how would I prove that it needs to be put in special measures? I would simply ask these three questions:

• Are Ofsted’s judgements accurate?
• Does it look at the right things?
• Does it actually improve our education system?

I think most teachers in this country know the answers to those questions... no, no, no.

Colin Harris led a school in a deprived area of Portsmouth for more than two decades. His last two Ofsted reports were “outstanding” across all categories

To read more of Colin’s articles, visit his back catalogue

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