One in four parents cited class size as important in a survey carried out by MORI for the Independent Schools Information Service last autumn. This is a rise from one in five parents in surveys conducted in 1989 and 1993. Discipline is now a factor for fewer parents.

The most commonly quoted reason continues to be that independent schools give “a better standard of education”.

More than half (52 per cent) of the parents had also considered state schools, a decrease since 1993 which is particularly marked among parents of girls and those sending children to single-sex schools. Class differences are becoming more polarised, with higher-income parents much less likely to consider the state sector.

A school’s reputation is more important to prospective parents than exam results. Only 16 per cent were concerned about school league-table positions.

Six out of 10 parents told MORI that their children’s opinion influenced their choice of school, with one third saying it influenced their choice “a great deal”.

Parents are increasingly likely to start their children in independent schools at an early age rather than trying the state sector first More than two-thirds of those entering prep schools last year had been to independent pre-prep schools, an increase from just over half in 1993.

More than half the parents of children at independent schools were not educated privately. Nearly one in four comes from social class C, D or E.

Many parents seem to be paying private-school fees (average day fees in ISIS schools are now pound;5,000 a year) on surprisingly low incomes. Just under a third of parents had gross incomes of less than pound;40,000 a year.

Currently 7 per cent of children are educated at independent schools. Between 8.5 per cent and 9 per cent are at independent secondaries, but the figure rises to 19 per cent by the sixth-form.