The saga of national tests is a ghastly mixture of good intentions, political empire-building and unintended consequences.
At first, Kenneth Baker's aims in establishing a national curriculum - although controversial - seemed perfectly sensible. It had become clear that Britain's standards of education were slipping against those of the rest of the world, as measured by international league tables.
In spite of the spread of comprehensives, teachers still seemed hung up on the notion of "ability," and their control over the curriculum meant that expectations were low. Many thoughtful educators welcomed the "entitlement curriculum". It meant that working-class children would no longer be fobbed off with a weak gruel which cut them off from the intellectual mainstream In the early days, educators were quite influential. Working parties of academics beavered away on the ideal curriculum for their subject. At first, the tests were called Standard Assessment Tasks and were supposed to be well-constructed real-life activities that were genuinely interesting and educative. But the pilot key stage 1 Sats were a disaster. Assessing 35 seven-year-olds on, say, a "floating and sinking" science task tested the skills of most Year 2 teachers to destruction. As one remarked wearily:
"Our main finding was that a banana which floats in the morning sinks in the afternoon." Supermarkets sold out of bananas. Pencil and paper suddenly looked more attractive - which suited the Conservative agenda.
Meanwhile, the task groups working on the curriculum had come up with an unwieldy behemoth, in which each subject fought for its own space and took no account of the others.
Schools found it impossible to shoehorn the content into the working day. A drastic slim-down - by Sir Ron Dearing, a non-educator - was ordered.
Needless to say, some of the most interesting aspects of subjects such as English and history disappeared in the resulting purge.
At the same time, the political agenda focused more and more on the tests results - as a way of improving the "market" in education. Consumers exercising choice, the Conservatives argued, needed better information on the quality of each school to choose the best. So test results and league tables came to dominate our lives. And once the media copped on to the opportunities for sensationalist headlines, a merry dance of exaggeration and hysteria began.
Although the tests were originally supposed to judge schools, not pupils, children were put under pressure by anxious teachers. Sats were presented to parents as judgments of ability. Pernicious phrases such as a "level 3 child" entered the language. Parents and children now talk of "passing" the Sats - an idea that ought to be nonsense.
This destructive process has been exacerbated by Labour's introduction of targets. The logic for doing so is hard to understand: Sats were calibrated to indicate what an average child could do. By turning the average into a target (a highly dubious procedure in statistical terms), the Government is demanding that 75 or 80 per cent of children put in an above-average performance.
Astonishingly, many schools have achieved this - showing that there was much untapped ability. But of course it can't go on for ever. And what has been the cost in sleepless nights, less time to play, and the loss of music and art?
Meanwhile, international tables show Britain is now near the top. In science, we are number three in the world. But no one seems to know, or care.