A NEW study from the Programme for International Student Assessment (PISA) will land on the desks of policymakers around the world next month. It will make sobering reading for political leaders in many countries. In Sweden Jan Bjorklund, the education minister, is prepared for poor marks too.

The triennial study by the OECD, a think-tank, measures the reading, maths and science proficiency of 15-year-olds. In the first study, in 2000, Swedish pupils performed a lot better than those in most other countries. But even as the country’s schools inspired imitators elsewhere, their results have deteriorated. In 2009 Sweden’s overall score fell below the OECD average. Other rankings show a similar trend.

"I assume the results will continue falling. It will take several more years before the positive effects of our policy begin to show in global ratings," says Mr Bjorklund, referring to an overhaul of Sweden’s education system. Since coming to power in 2006, the centre-right coalition government has introduced reforms such as a new national curriculum. Mr Bjorklund, who heads the Liberal party, is convinced he can reverse the decline. But will voters have the patience to wait? With universities complaining that students arrive unprepared and companies worrying that Sweden will lose out to other countries, a sense of urgency is in the air. Education will be important in next year’s election.

What went wrong? Money is not the problem. Free education from primary school to university has long been a pillar of Sweden’s welfare system, and public spending on education is among the world’s highest, according to the OECD (see chart). Immigration is high, though this according to Skolverket--the National Agency for Education--had only a marginal effect on overall results.

Mr Bjorklund blames the poor results on the period when the Social Democrats were in charge. Others say poorly paid teachers are at fault. The profession, once highly regarded, has seen salaries fall far behind other jobs requiring a higher-education degree. The student demand for teaching programmes is so low that almost anyone applying will be accepted. As many teachers approach retirement, unions warn of a teacher crisis ahead. In hopes of making the job more attractive, a career programme with better pay was launched this year.

A growing gap between schools is another reason, says Skolverket. Sweden is now one of the few countries to show both worse results and more inequality. Free school choice is a contributing factor. The system, introduced 20 years ago, allows parents to choose between municipal schools and independent schools, all financed by tax money. The aim was to increase quality by competition, but it has also led to the best students flocking to the same schools.

Many worry that school inequality will spur segregation. Extra resources for schools with weaker students could be a solution but abolishing independent schools is not on any party’s agenda. Polls show a majority of Swedes want to keep the free-school choice. Still, letting private companies run tax-funded schools is controversial. Critics say profit-seeking puts quality at risk. In the wake of several school companies’ bankruptcies, the government has indicated that private-equity funds will no longer be welcome owners.

The PISA study, due on December 3rd, will make headlines. But educationalists say such rankings don’t give the whole picture. Swedish students are good at social science, history and English. Democratic values and gender-equality permeate the curriculum. Those are important, to be sure, but they are of little solace to exporters in need of engineers.

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