CLAIRE COLLING has been a teacher for 23 years and has never had to put in the hours she does now. Her work begins at around 7am and sometimes does not end until 10pm, when she finishes marking and preparing lessons slumped in front of the television. Making sure that classes meet the needs of all her pupils—from high-flyers to stragglers—is tough. But it is not as tough as marking, which takes up “an inordinate amount of time”, partly because of rules imposed from above. “I never thought I would be micromanaged to such an extent that I would be told what colour pen to use,” she says. Ms Colling is not the only Stakhanovite in English schools. Indeed, her hours are not that far from the norm. Teachers in England and Wales are among the busiest in the world (see chart). Each day, they work an hour and a half longer than the average reported by their colleagues in other countries; only Singaporean and Japanese teachers are more dedicated. English teachers also spend an unusually high proportion of their day on marking and administration. Such activities take up 30% more time in English schools than in most of their international equivalents.

At first glance, it seems that English teachers are reasonably well paid for their efforts. According to analysis by The Economist, their salaries, adjusted for hours spent at school and compared with those of similarly-qualified graduates, are around the average for the OECD club of mostly rich countries. But English teaching contracts are flexible: although they state that a full-time teacher must work a relatively puny 1,265 hours a year, teachers must also put in “reasonable additional hours” to plan lessons, assess pupil performance and mark homework. And what may once have been reasonable now looks increasingly unreasonable. According to the Department for Education, which analysed teachers’ diaries, the time teachers spent marking nearly doubled from 2010 to 2013. Altogether, teachers worked seven hours more a week than they did in 2010.

The rise in teachers’ workload is partly a result of the long-running trend to focus on the performance of each pupil rather than that of the class as a whole at the end of the year, says John Howson of Oxford University. The situation has been exacerbated, however, by government tinkering with exams and the curriculum. The move to supervised coursework for GCSEs, the qualifications taken at 16, and to teacher assessment in primary schools has caused difficulties, says Daisy Christodoulou of Ark, a high-performing academy group. Partly for this reason, supervised coursework is to be phased out from this year. Further changes to GCSEs and to A-levels, exams taken at 18, are still to come into effect. “A more consistent approach from government would help,” sighs one primary-school headteacher.

But bad management in schools is also a problem. Many teachers are overwhelmed by poor-quality data-collection, unnecessary marking and formulaic lesson planning. A forthcoming report by the Education Endowment Foundation, a charity, will warn that there is little research to back many popular marking strategies. And teaching fads are still widespread, notes Jonathan Simons of Policy Exchange, a think-tank, with schools often motivated by myths of what inspectors are said to look for.

The intense workload is not just bad news for teachers. Schools are finding it increasingly difficult to recruit them, and shortages are exacerbated by a rise in the number of those leaving the profession. In 2014 10.4% of teachers quit their jobs, up from 9.6% in 2011. It seems that few are moving for more money: according to the National Foundation for Educational Research, a charity, about as many leave to become teaching assistants as to go into the private sector.

Most educationalists reckon the government has grasped the extent of the problem. The Department for Education recently published a series of reports on how to reduce teacher workload, which were pragmatic but offered few concrete solutions. Ofsted, the schools watchdog, has clarified that it focuses on outcomes rather than processes. But rising pupil numbers and a falling schools budget mean that such efforts are likely to be in vain. That is unfortunate: too many teachers currently work like students cramming for final exams. And as many former students can attest, there are better ways to get results.