THE children at Kulosaari primary school, in a suburb of Helsinki, seem unfazed by the stream of foreign visitors wandering through their classrooms. The head teacher and her staff find it commonplace too—and no wonder. The world is beating a path to Finland to find out what made this unostentatious Nordic country top of international education league tables. Finland's education ministry has three full-time staff handling school visits by foreign politicians, officials and journalists. The schools in the shop window rotate each year; currently, Kulosaari is on call, along with around 15 others. Pirkko Kotilainen, one of the three officials, says her busiest period was during Finland's European Union presidency, when she had to arrange school visits for 300 foreign journalists in just six months of 2006.

Finland's status as an education-tourism hot spot is a result of the hot fashion in education policy: to look abroad for lessons in schooling. Some destinations appeal to niche markets: Sweden's “voucher” system draws school choice aficionados; New Zealand's skinny education bureaucracy appeals to decentralisers. Policymakers who regard the stick as mightier than the carrot admire the hard-hitting schools inspectorate and high-stakes mandatory tests in England (other bits of Britain have different systems).

But visitors to Finland—and to a lesser extent to South Korea, Hong Kong, Taiwan, Japan and Canada—are drawn by these countries' high scores in a ranking organised by the Paris-based Organisation for Economic Co-operation and Development (OECD), a rich-country think-tank. Its Programme for International Student Assessment (PISA) tests 15-year-olds from dozens of countries (most recently 56) in literacy, mathematics and science. Finland habitually comes top; the others jockey for places as runners-up (see chart).

Such a quest is understandable but misguided, says Alan Smithers, an expert in cross-border education comparisons at Britain's University of Buckingham. Importing elements of a successful education system—the balance between central and local government, the age of transfer to secondary school, the wearing of school uniforms and so on—is unlikely to improve performance. “You shouldn't try to copy the top performers in PISA,” he says, “because position in those league tables depends on lots of other things besides what happens in schools.”

Bearing out Mr Smithers's caution is an analysis of Finland's most recent PISA results, from 2006, by Jarkko Hautamäki and his colleagues at Helsinki University. They highlight only one big policy element that could easily be replicated elsewhere: early and energetic intervention for struggling pupils. Many of the other ingredients for success that they identify—orthography, geography and history—have nothing to do with how schools are run, or what happens in classrooms.

In Finnish, exceptionally, each letter makes a single logical sound and there are no irregular words. That makes learning to read easy. An economy until recently dependent on peasant farming in harsh latitudes has shaped a stoic national character and an appetite for self-improvement. Centuries of foreign rule (first Swedes, then Russians) further entrenched education as the centrepiece of national identity. So hard work and good behaviour are the norm; teaching tempts the best graduates (nearly nine out of ten would-be teachers are turned down).

Few countries would want to copy Finland's austere climate or sombre history even if they could (though spelling reform in English might merit consideration). More instructive, perhaps, is looking not at how Finland's schools are run, but how decisions about education are made. As in other European countries, Finland merged specialist academic and vocational schools into comprehensive ones in the 1970s. The first point Mr Hautamäki highlights is broad consensus, cautiously but irrevocably reached. “They simply kept going until they reached agreement,” he says. “It took two years.”

Comprehensive schools were introduced in 1972 in the sparsely populated north, and then over the next four years in the rest of the country. Matti Meri, a teacher-trainer at Helsinki University, was a teacher at the time. “Grammar-school teachers were quite afraid of the reforms,” he recalls. “They used to teach only one-third of the students. But the comprehensive schools used almost the same curriculum as the grammar schools had—and we discovered that the two-thirds were mostly able to cope with it.” By the time comprehensives reached the more populous south, teachers were eager to join in what was clearly a roaring success.

“What you are planning might be the right thing to do, but if teachers aren't on board it will be very hard to make anything happen,” says Sam Freedman, the director of education for Policy Exchange, a London-based think-tank. He points to Canada, where Alberta and Ontario both introduced major reforms in the 1990s. Alberta's provincial government won general support for its ideas, and the reforms are now uncontentious. In Ontario, by contrast, politicians' rhetoric was confrontational and the teachers' unions bitterly opposed. The current government is having to work hard to mend fences.

Finland's education reforms may have taken ten years from conception to full implementation, but they have proved durable: little has needed changing in the 30 years since. Mr Smithers draws a gloomy contrast with the permanent revolution that reigns in England's schools. “Politicians here seem to think that a day without an education announcement is a day wasted,” he says. New policies should build on previous ones, agrees Andreas Schleicher, the OECD's head of education research. “In some countries, though, a new government's greatest ambition is to undo everything its predecessors did.”

Mr Schleicher acknowledges that the hopeful, or simply naive, sometimes rifle through the PISA studies for shiny new education initiatives to pilfer. But, he says, international comparisons teach a crucial lesson: what is possible. “In 1995, at the first meeting of OECD ministers I attended, every country boasted of its own success and its own brilliant reforms. Now international comparisons make it clear who is failing. There is no place to hide.”