The NAO is not in the business of excusing failure. Its role is to promote greater efficiency. Nor can Ofsted claim to have been unaware of the need to make more meaningful comparisons. The TES reported in 1996 that HM Inspectors were going to do just that. But the plan was disavowed by the then chief inspector, Chris Woodhead. And not until last year was a value-added element belatedly included in league tables.
The report concludes that Ofsted's school ratings have continued to follow the raw results rather than show the extent to which schools were overcoming low prior attainment and disadvantage. The enormity of that misjudgment is now clear. One in 10 of the bottom 20 per cent in 2002 should in fact have been rated among the top 20 per cent of schools for effectiveness in GCSE, once such background factors were allowed for.
The cost of this policy is hard to quantify. The NAO and Ofsted agree that what makes a difference in schools is good leadership and teaching and a positive ethos. But how much more difficult has it been to attract good leaders and teachers and to stay positive in schools facing not only social and economic challenges but also an inspection and assessment system loaded against them? Is it a wonder the achievement gap has widened?
Those who teach in adverse circumstances deserve recognition for success against the odds, not a periodic rubbishing of their efforts from inspectors and an annual kick in the teeth from the league tables.