Independents are outshone by state grammars in A-level results

State grammar schools took the top two places in this year's A-level league table, beating all of those in the independent sector.

The top performer was Colchester Royal Grammar School in Essex, which is boys only until the age of 16 but admits girls in the sixth form. Its pupils notched an individual point score of 1,354 – the equivalent of about five A-grade passes for every candidate.

The results will fuel the campaign by some Conservatives for a return to selective schooling, and could pose problems for a David Cameron-led administration. The Tory leader is opposed to the creation of new grammar schools, against the wishes of some members of his party.

Second place in the tables went to Colyton Grammar school in Devon with 1,330 points. The leading independent school was Hampton near Twickenham with 1,319.

The overall figures confirmed that state grammar schools achieved higher scores on average than those in the independent sector. Their pupils had an average point score of 964.5 per pupil, equivalent to three As and a C, compared to 890.9 in the independent sector.

However, a closer analysis reveals that the grammar schools only remain ahead by cramming their pupils in for more exams.

On a measure which reveals pupils' point score per subject entry, the independent schools score 238 points while grammar schools gain 228. Yesterday's league tables also confirm that top fee-paying schools such as Eton and Winchester lie at the bottom of the GCSE league tables.

In all, 145 independent schools failed to score at all in the tables because they enter their pupils for International GCSEs, which are designed along the lines of the old O-level and place more emphasis on end-of-term examinations.

The exams are not recognised by the Government which says they do not conform to the national curriculum. Many in the independent sector claim this makes "a nonsense" of the league tables.

David Lyscom, chief executive of the Independent Schools Council (ISC), said: "The comparison of school performance via league tables is deeply flawed. ISC calls on the Government to ensure that the worth of all relevant qualifications is fully recognised... otherwise they simply serve to misinform and mislead parents."

The Conservatives have said they will recognise International GCSEs if they win the general election.

Chris Keates, general secretary of the NASUWT, the largest teachers' union, said: "Teachers and all school staff have continued their relentless drive to continue to raise school standards.

"Particular attention should be focused on the progress made by the state system relative to that seen in the independent sector. Today's results provide firm evidence that state schools offer a high-quality, diverse and engaging educational experience for all pupils from all backgrounds and circumstances."