NEW GCSE data released today has shown huge differences in how well schools support pupils of differing abilities.

For the first time, the Department for Education has published data showing how youngsters performed in their GCSEs compared to expectations set for them five years earlier.

The new tables measure how many pupils judged to have low, average and high attainment in their Key Stage Two tests aged 11 who went on to achieve the expected progress aged 16.

It was the first year that Oxfordshire’s GCSE performance fell below the national average, with 57.4 per cent of pupils getting give A* to C grades including English and maths, compared to 58.2 per cent across England.

But six of the county’s best private schools once again made it into the list of the country’s top performing schools.

St Helen and St Katharine in Abingdon was ranked the 56th best school in the country based on its GCSE results, with Oxford High School, Our Lady’s Abingdon, Magdalen College School, Abingdon School, and Radley College also appearing in the top 200.

At The Oxford Academy, which achieved the lowest results in the county, just 19 per cent of low achievers and 50 per cent of high achievers made the expected progress in English, while 26 per cent of low achievers and 67 per cent of high achievers made the predicted grades in maths.

The academy was the only school to fall under the Government’s minimum targets for GCSE results, with 28 per cent of pupils getting five A* to C grades including English and maths at GCSE.

National tables ranked the school as having the 35th worst results in England.

But even among high-performing schools, there was a big gap in maths and English performance.

Among Oxfordshire pupils with low attainment rates in their Key Stage Two exams, 48 per cent went on to fulfil their expected potential at GCSE. But in maths, just 26.8 per cent made the expected progress, reflecting a national achievement gap.

Just 126 of the 502 GCSE pupils Oxfordshire receiving free school meals achieved five good grades including English and maths. That compares to 33.9 per cent nationally.

But among youngsters not receiving free meals, 60 per cent made those grades in Oxfordshire.

And the percentages of disadvantaged children making the expected progress in English and maths between the ages of 11 and 16 vary wildly between schools, from 0 per cent to 75 per cent.

* Tables showing results will be published in Friday's Oxford Mail.