Grammar schools are creating “ghettos of the advantaged” and do not provide “ladders of opportunity” for the poor, research suggests.

The findings, from David Jesson, of the University of York, indicate that a significant number of parents are effectively “buying” their way into grammar schools by paying for their children to be coached for grammar school entrance exams, either by private tutors or at private prep schools.

Professor Jesson said that the findings suggested that grammar schools were doing little to alleviate the social and economic divisions in society they were intended to serve.

His research also questions the value of the immense personal sacrifices made by parents to get their children into grammar schools, as it indicates that the vast majority of them do little better than comprehensive schools at helping pupils to progress through their GCSEs.

The findings, published today by the Centre for Market and Public Organisation, an influential research institute, are bound to fuel the fierce public and political debate about the merits of selective education.

David Cameron insists that a Conservative government would not return to school selection at 11, although he has said that the existing grammar schools will be able to expand.

The Government has indicated that it is considering making it easier for parents to force the closure of local grammar schools. Professor Jesson measured grammar recruitment against three levels of poverty or wealth: eligibility for free school meals, the Income Deprivation Affecting Children Index (the proportion of children under 16 in an area living in low-income households); and the proportion of pupils previously attending fee-paying schools.

He found that only 2 per cent of grammar schools pupils are on free school meals (FSM), even though FSM children make up 12 to 14 per cent of the school population in their areas.Professor Jesson said: “Taken together, this evidence shows clearly how far grammar schools are from providing the ladder of opportunity for children from disadvantaged backgrounds that many of their supporters claim. Indeed, a more appropriate description might be that they are ghettos of the advantaged.”

He found that the majority of grammar schools, 129, provide no better than average progress for pupils. Only 19, 12 per cent of the sector, provided above-average progress.

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