Lifetime's struggle for sake of £33 a week

The difference between them is, at most, 33 a week. This is because the amount Glasgow City Council spends per pupil on education is 4,800 a year: fees for Hutcheson Grammar are 6,200. The financial gap is tantalisingly close - but, to council-estate children, unbridgeable.

This is a political decision. There is a consensus in the Scottish Parliament - from every party - that the money allocated by the taxpayer for educating state-school pupils must be spent by government officials on government schools.

To visitors from the Netherlands, Denmark or Sweden this is astonishing: why this divide between the rich and the poor? If the taxpayer has willingly directed money to families, why should bright children not get a chance at the best schools?

These countries use the voucher system - where parents decide where their 4,700 should be spent. Except it is far less on the Continent: but this is more than enough for teachers to open their own schools and make things work.

Wherever it has taken hold, the voucher system has worked. By making parents into the "education tsars", the good schools have been rewarded and the poor ones closed down. It has proven popular in every area.

But in the UK, it remains so contentious that not even the Conservative Party dares to suggest that the 4,700 set aside by the taxpayer to educate every Scottish child could be used to help the disadvantaged receive a better education.

It is a market for education, critics argue - this only works if supply outstrips demand. And Scottish schools are all full: the private schools have waiting lists - given the vouchers, where would the children move to?

Here lies Scotland’s opportunity - and threat. The first sign of depopulation is an exodus of youth. This year, officials believe Scotland will lose 12,600 school places which will never be replaced.

The decline grows faster: a further 14,200 school places will go. There will be lots of spare capacity in the system - but, as things stand, officials intend to close this down. The Scottish Executive’s plan is to axe teaching jobs at the rate of 630 a year from 2008.

As things stand, the state-run system (where supply meets demand) will see 3,500 teaching jobs being axed over the next ten years. These are the official plans, as they stand.

The alternative is taking a radical new look at the way secondary education is managed - and asking if whether this surplus of school places could be the launch-pad for a market-based system where parents choose the schools - and the teachers run them.

Scotland’s starting block is generous: 4,700 a head. This is what the average local authority has to spend on state-school pupils.

The last published figures from the OECD show Scotland makes the world top five for education spending - towering above higher-taxing countries such as Norway, Denmark, France and Germany.

The 4,700 is also not so far away from the 6,170 charged by Glasgow High School or the 5,712 charged by St Margaret’s private school in Edinburgh. The point: this kind of money should be buying seriously good education.

Which makes it harder to explain why, in Edinburgh, 4,733 buys a place at Wester Hailes - its academic record the worst in Scotland, where only a third of pupils secure more than five passes at Standard Grade at level four or better.

Yet for those who can afford to live in the right catchment area, Edinburgh City Council’s 4,722 per pupil buys Boroughmuir High and James Gillespie’s High - which last year had equivalent pass rates of 87 per cent and 86 per cent respectively.

This is the comprehensive system: and, to those with children in Wester Hailes, Govan High or Braeview Academy in Dundee, there is nothing equal about it. It is such children that the voucher system is intended to help.

Ohio, Florida, Vermont and Wisconsin are among American states which decided to give black children money to attend private or specially "chartered" public schools. It was deemed to be their route to break out of the ghettos.

While polls showed that 69 per cent of blacks support vouchers, Democrats have dismissed the Republican plan as a "tax break for parents who already have children in private schools".

But attempts to draw a left-right divide over vouchers have one problem: Sweden, arguably the most left-wing country in Europe, uses the voucher system wholesale.

Since it adopted the voucher system in 1992, it raised the limit to the average state-school fee - and the results have won over the socialists. The number of independent schools increased fivefold: supply shot up. Good teachers can now set up their own school - and are paid about 3,000 for every child they take on. Schools do not have the right to cherry-pick: they must accept pupils on a first-come, first-served basis.

The results: Attendance in classes quadrupled where parents moved schools. Teachers reported an improved climate for teaching. Ask a Swedish politician if this is a right-wing scheme and they will say it is empowering parents and teachers paid dividends.

Yet in Scotland, political opposition remains entrenched. Ken Macintosh, a Labour MSP member of Holyrood’s education committee, speaks for many - including in the Scottish National Party - in saying that vouchers "undermine the state sector".

"The voucher system is an ideologically-driven idea based on the idea that private schools are better than state schools," he says.

"They subsidise private education for very few, and it simply does not create more choice at all."

But mass school closures may focus minds.

With 4,700 a head to spend on working-class children, there is no financial reason for any Scottish child to languish in a sink school.

The only remaining obstacle is political inertia.