Most of those parents would probably be shocked to learn the truth behind this phenomenon. On average, a child at primary school receives just 73p for every pound spent on his older brother at the secondary school down the road. In some areas a 10-year-old costs £1,500 less per year to educate than an 11-year-old.
League tables published last week by the Audit Commission show that the national figures mask huge discrepancies between councils. While Camden and Durham spend 90p on their primary pupils for each pound spent on secondary, Haringey spends just 57p and Wandsworth 59p. Perhaps parents would be even more shocked to know that in more than 60 years since the problem was first acknowledged, little has been done about it.
These words from an official report can rarely, if ever, have been disputed: "We should deprecate very strongly ... any tendency to make the improvement of the schools attended by older children an excuse for offering inferior accommodation to children under the age of 11, nor can we accept the view that classes in primary schools may properly be of a larger size."
This warning was addressed not to the current government, nor to its predecessor. It was sounded in the Hadow report on primary schools, published in 1931.
Thirty-six years later, when Lady Plowden published her report on the under-11s, little had changed.
"Nobody ought to be satisfied with the conditions under which many ... primary children are educated. Primary education ... is failing to secure its share of educational and national resources," she wrote.
Another 21 years then went by before the House of Commons Select Committee on education reported on the issue in 1986. Professor Robin Alexander of Leeds University, who provided the Independent with quotes from Hadow and Plowden, pointed out then that both had made the same complaint with little effect.
"The primary-secondary anomaly has arisen from a century of casual and rarely questioned belief that primary education is less significant for the child than secondary, and that primary teaching requires less professional knowledge and skill. This must be exposed for the myth that it is," he wrote more recently.
He believes that history is to blame, and that attitudes have changed little since elementary schools were set up in the 19th century to provide basic education for the children of the poor. In 1862, the vice-president of the government's Education Department, Robert Lowe, told Parliament that if the schools were not efficient, they should at least be cheap. Many commentators believe that the administrators of the modern education service still cling to this view.
A second select committee report last year on the disparity of funding between primary and secondary schools called for the Government to fund major research on the problem, but none has been initiated.
Doug McAvoy, general secretary of the National Union of Teachers, is one of many people who have continued to call for action while emphasising that increased spending on primary education should not be at the expense of secondary schools.
"It is appalling that when children are in their most crucial period of teaching and learning, funding is not there to ensure the possibility of individual as well as cross-class teaching to start them off on the right road," he says.
The Government said in response to last year's report that decisions on how to fund primary and secondary schools should be left to local authorities, and ministers have had little to say on the subject since. Ironically, perhaps, they have not chosen to blame local authorities for the problem as they did in the more recent dispute over education cuts.
In fact, many local authorities have been trying to redress the balance. A sophisticated analysis of education spending since 1979, carried out for the Independent recently by the House of Commons library, shows that this has been happening for the past 16 years.
When spending is analysed to take account both of inflation in the education sector and of fluctuations in pupil numbers, it is revealed that secondary school spending is actually falling. In real terms, primary school pupils received 15 per cent more money in 1992-93 than they did in 1979-80, while secondary pupils received 5 per cent less.
But despite these adjustments, which may have more to do with the introduction of the National Curriculum than an attempt to address the unequal spending balance between primary and secondary, we still spend a third more on secondary pupils than on primary pupils.
Educationists have been saying since 1931 that something should be done. Thousands of parents, teachers and governors of primary schools hope it will not take another 65 years before the funding gap is finally closed.