In a classroom in Seoul a throng of teenagers sit hunched over their desks. In total silence, they flick through a past exam paper. Stacks of brightly coloured textbooks are close to hand. Study begins at 8 a.m and ends at 4.30 p.m, but some won’t go home until 10 p.m. Like hundreds of thousands of South Koreans, they are preparing for the suneung, the multiple-choice test that will largely determine whether they go to a good university or a bad one, or to university at all.

Over the course of a single generation, degrees have become close to ubiquitous in South Korea. Seventy percent of pupils who graduate from the country’s secondary schools now go straight into university, and a similar percentage of 15-34-year-olds hold degrees, up from 37 percent in 2000. Students scramble for admission into the most prestigious institutions, with exam preparation starting ever younger. Sought-after private nurseries in Seoul have long waiting lists.

South Korea is an extreme case. But other countries, too, have seen a big rise in the number of young people with degrees. In the OECD club of 35 countries, 43 percent of 25-34-year-olds now have degrees. In America, the figure is 48 percent.

Policymakers regard it as obvious that sending more young people to university will boost economic growth and social mobility. Both notions are intuitively appealing. Better-educated people will surely be more likely to come up with productivity-boosting innovations. As technological change makes new demands of workers, it seems plausible that more will need to be well-educated. And a degree is an obvious way for bright youngsters from poor families to prove their capabilities.

In the meantime the decision not to go to university remains risky, even though many graduates will end up doing work that used to be done by non-graduates — or struggle to find a job at all. Around half of unemployed South Koreans now have degrees. For them, the very concept of a “graduate premium” may seem a mockery. Kim Hyang Suk, a recruiter in South Korea, says that half the applicants for customer-service jobs at her firm are graduates, even though only a secondary-school education is specified.

She would prefer school-leavers with experience, says Ms. Kim, to inexperienced graduates whom she will have to train. She is not looking for swots, but people who are “engaging, good on the phone”. But when few employers are this open-minded, most young people will want a degree. It may not boost their earnings as much as they had hoped, but without one, they would probably fare even worse.

(Excerpted and adapted from The Economist and Times Higher Education)