India has shown it can take bold political decisions. Delhi banned diesel from fare-charging vehicles and public transport to tackle pollution a year before Ken Livingstone introduced London’s controversial congestion charge.

Gone are the famously rusting buses, black and yellow taxis and scooter rickshaws belching out black smoke. In their place are shiny new versions ringed with a green stripe to show they run on compressed natural gas.

By comparision, overhauling the education system of a country with a billion people and nearly a million schools is a challenge of gargantuan proportions. But that is exactly what its education minister claims to be doing.

“It’s a huge job,” concedes Professor Murali Manohar Joshi, minister for human resources development (HRD), at his Hilton suite in Edinburgh, where he is attending the Conference of Commonwealth education ministers.

Since education is one of two briefs inside HRD, along with women and child development, and he also holds the ministries of science and technology and ocean development, one can only wonder where Professor Joshi, 70, finds the time and energy to devote to it.

Two years ago he tabled a constitutional amendment, which came into force in April, giving every child aged six to 14 the right to free education. A nationalist Hindu hardliner in the ruling coalition, he unveiled a national action plan to achieve education for all to be backed by an extra $20bn of taxpayers’ money over 10 years.

“Education is a liberating force,” he says. “It is not just about creating skills, which is very important, but it is to liberate you from the bondages, from the shackles, and to create an open mind.”

However, educating the world’s largest out-of-school population - 40m of the estimated 104m total worldwide, based on government figures for 2001 - is made more daunting by the variety of obstacles to progress.

One system will not fit easily into a society divided starkly between rich and poor.

A rising middle class, encompassing the software engineers of the burgeoning computer industry and the graduate call-centre workers dealing with our water and credit bill problems from Bombay and Delhi, is already well educated.

But tens of millions of children of slum dwellers, peasant farmers and nomads, many of them child labourers themselves, have had no chance to go to school. For them, fees and incidental costs, such as meals and uniforms, force them to choose between sending their children to work or to school, between schooling sons or daughters.

The reasons are part poverty and part the shambolic state of India’s investment-starved education system.

An independent report, cited by Oxfam, says that in 2001 one in six primary schools had no building and were operating in thatched huts, tents or under a tree. One in 10 schools had no instructional room at all, two-thirds had only one or two rooms, one in two had no drinking water, and four out of five had no toilet.

Joshi, a professor of physics for 40 years at Allahbad university in Uttar Pradesh in India’s Hindu belt, who alienated Muslims with attempts to Hinduise the curriculum, blames these problems on the colonial legacy.

“The state of education is a result of British rule,” he says. “When they first came here India was more literate.”

The British destroyed the indigenous system, he says, by refusing to recognise certificates of any school not controlled by them.

“Indian education was not run by the governments, it was run by the community. They said these schools will get no grants.”

Professor Joshi rattles off a plethora of schemes that are trying to plug the gaps: vocational training for school drop-outs; a national open school for child labourers; national campaigns to tackle adult illiteracy - two-thirds of them are women; and extra support for the one million volunteers providing pre-school activities, health and hygiene care to infants.

The linchpin of his plan, though, is an attempt to switch control of schools to the village level and speed up the establishment of new ones, even if it means starting under a makeshift shelter.

The 75 per cent of funding for schools from the central, federal government is being sent directly to school trusts, by-passing local state administrations, to cut back on red tape. Village committees (panchayats) appoint teachers, choose the location of the school and manage the running of them.

“Any habitation with no school within one-and-a-half kilometres will be given a teacher and learning and reading materials. And if the system works for three years, if we can be sure the villagers are really serious about education, we incorporate the school into the (national) system.”

He says in the past two years the government has cut the number of primary children not at school by 20m and the target is to get the remaining 20m of the 190m six to 14s in by the end of the year.

Seema Gaikwad, co-ordinator of the Commonwealth Education Fund in India - set up to mobilise demand for education among parents and non-governmental organisations and encourage their involvement in running schools - says this is “pure fantasy”.

While the government has made great efforts to get children into school, she says, too little is being done to shore up the quality of teaching, because teachers of grades 1-5 have not studied beyond secondary school, and pupils are dropping out. The real number out of school may be nearer 100m, a charge that Professor Joshi dismisses out of hand.

He is equally caustic about the World Bank’s Fast Track Initiative, a global scheme to raise money from wealthy countries for developing countries’ national education plans.

It was dubbed the education equivalent of Bush’s road map for the Middle East by Commonwealth education ministers at Edinburgh last week, who behind the scenes were fizzing with anger at the rich countries’ failure to speed up funding.

“I was very disappointed with the attitude of the G8 countries,” Professor Joshi says. “They must fulfil their promises. We have changed our constitution and enacted laws. They must also come on board.”