Elite prep schools are becoming training grounds for the best state schools as the recession forces parents to opt for selective grammar schools when their children reach the age of 11.

In a survey seen by The Times, a quarter of prep school head teachers said that there had been a rise in the number of pupils going on to grammar or other state-maintained schools for their teenage years.

Parents are also increasingly choosing to invest in their child’s education early on to avoid the higher, more prolonged costs of senior private schools, reversing the trend among the middle classes to pay for school only once pupils have been through a local primary. It will put pressure on parents at state primaries to employ tutors in order to compete for places at selective grammar schools.

Applications to take the 11-plus have increased in 70 per cent of grammar schools, according to a separate survey conducted by The Times. Packed open days and late flurries of applications are also reported.

Professor Alan Smithers, director of the Centre for Education and Employment Research at the University of Buckingham, said that the move to invest earlier rather than later in children’s education was a logical one.

“Private education is getting relatively ever more expensive and there is a growing recognition of the importance of early years,” Professor Smithers said. “So parents are investing in a good prep school education in the hope that they will ... put their sons and daughters in a good position to get into a grammar school or a leading comprehensive school, which are often selective.

“It seems to me to be a logical way of reacting to the [economic] circumstances and the great importance of the first years of education.”

Prep schools can cost £7,500 a year for day pupils, compared with £18,000 a year at top public schools. Fee rises also differ, with average increases of 2.95 per cent a year in prep schools compared with 3.4 per cent in elite independent senior schools.

Four of the top ten schools at GCSE this year were grammars, the others were independents. Figures from the University of Cambridge show that one in three state school pupils at the university comes from a grammar school. Only 164 of the 3,000 secondary schools in England are grammars.

Julie Robinson, head of Vinehall School, East Sussex, and vice-chairwoman of the Independent Association of Prep Schools (IAPS), said that prep schools would benefit from the switch to earlier investment. “Particularly in areas where there are still grammar schools, parents are willing to invest in the foundations of their child’s education with a view to moving their child into grammar type schools,” she said.

Smaller prep schools had been seen as taking the hardest knocks in the credit crunch with a number forced to close as pupil numbers dwindle.

The IAPS found that 26 per cent of prep schools had increasing numbers of pupils going on to state schools. In 42 per cent of prep schools, numbers have decreased on last year, but the average loss is less than one pupil per school. It is the first time that the IAPS, which represents 600 schools, has carried out such research.

Competition for grammars is stiffer than ever this year. In Kent 11,873 children registered to take the eleven plus, up 7.39 per cent on last year. Thousands of those are believed to have been from outside the county in areas without grammar schools. Essex had a similar increase of 6.7 per cent on last year and thousands are hoping to get places in Warwickshire, Birmingham and Buckinghamshire.

The Times surveyed 39 grammar schools. Of the 24 that responded, all said that interest was up or at the same level as last year.

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