Richard Garner: New league tables reveal pupil progress

They're secondary school performance league tables, Jim, but not as we know them. This new version of the famous catchphrase from the TV show Star Trek is probably the best way to describe the new-look league tables published today by the Department for Education and Skills (DfES). The most obvious difference is that there are no A-level results. These have been delayed because of last summer's regrading fiasco and are not expected to be published before April.

However, the biggest difference in this year's league tables is that they represent the first serious attempt to introduce a "value-added" element by showing how much progress each school makes with the pupils they take in at the age of 11.

For this year – and this year alone – there are two separate value added measures. The first shows the relative progress made by schools with pupils between the ages of 11 and 14 and the second the progress made between 14 and 16. For reasons of space, we have chosen to publish the second measure, on the grounds that parents are more interested in standards at GCSE.

There are obvious flaws in having the two measures. A school could be lousy in the first three years of secondary education and then improve dramatically in the final two years before GCSE. It would score badly in the first measure but do well in the second.

The obvious way to show how much progress a school has made with its pupils is to have one measure showing progress over the child's lifetime at the school. That, we are told, will be produced next year but the technological data is not available this year.

A word is needed about how the value-added measure is calculated. An average performance would give a school a score of 100. Anything above that is a sign of good progress with pupils. However, officials have issued a health warning – saying that the smaller the number of pupils the less confidence one can have in the value-added measure. Therefore, for schools with 50 or more pupils, a score of 95.8 to 100.8 is average, but for schools with more than 100 the average is between 96.5 and 100.1. Only eight schools in the country appear in the top five per cent of those adding value at age 11 to 14 and at 14 to 16. Of these, four are independent, two are selective grammar schools and two are comprehensives.

A list of the best-performing 300 schools in both tables includes a far higher percentage of grammar, independent and girls' schools. Boys' schools hardly figure. Professor David Hopkins, the head of the DfES' Standards and Effectiveness Unit, argues that the grammar schools do well because they have an intake of high-ability pupils who thrive off one another. But other studies, notably from Professor David Jesson, of York University, suggest that – overall – areas with comprehensive schools do better for the range of pupils they serve than areas in which pupils are selected.

With so many caveats over how the information should be interpreted, it may be a case of roll on next year when there will be one agreed way of ranking schools on how much value they add to a pupil's performance.

The writer is Education editor of 'The Independent'