BRIGHT youngsters are being let down by state school education, according to research carried out by a York-based academic.

Professor David Jesson, of the University of York, tracked the progress of 28,000 children in England with the highest marks in national English and maths tests that they took, aged 11, in 1999.

Prof Jesson, a key government advisor, found that children in the top five per cent nationally for academic ability did far better in schools where they were grouped together.

But in schools that did not have as many of these top pupils, bright children achieved much lower exam grades, according to the study for the Specialist Schools Trust.

About 12,000 pupils went on to study at the same 400 selective grammar schools or top-rated comprehensives.

But the other 16,000 were spread across 2,400 comprehensives, many of which were in urban areas and had poorer academic records.

When these 28,000 pupils took their GCSEs last year, Prof Jesson found their results varied, depending on how many bright pupils were in their year group.

Where 20 of these bright pupils were in the same year group at the same school, they scored an average of nearly seven A* or A-grades each at GCSE.

But in schools where only one of these 28,000 top pupils was taking exams, the pupil scored fewer than four GCSEs at the highest grades.

Jenny Vickers, City of York Council's assistant director of education standards and quality, said that in many York secondary schools children were streamed according to ability.

She said: "While we are always interested in research like this, to make such sweeping generalisations is unhelpful and not supportive of educationalists and students generally.

"The aim of all schools is to ensure that they are providing educational opportunities to meet the needs of all ability groups, and children who are able, gifted and talented deserve to have their educational needs met within that."

The study was commissioned by Sir Cyril Taylor, the chairman of the Specialist Schools Trust, and an adviser to Education Secretary Ruth Kelly.

He said: "If you have only one or two children of high ability, then they get lost in the system and don't get the support they need.

"A lot of these kids are not delivering their potential."

The study found that pupils in top state comprehensives tended to get slightly better grades than their counterparts in grammar schools.

Sir Cyril said top pupils could be identified from their primary school tests, and then given extra attention at secondary school to make sure they fulfilled their potential.

Updated: 10:25 Tuesday, May 24, 2005