Some 290 high schools across Japan, most of them publicly run, were found to have not taught all compulsory subjects to students. More than 47,000 students have been affected. Third-year students who will take university entrance exams early next year will especially be in a tight spot. To be able to graduate, they may have to take extra classes during the winter vacation -- a time usually spent preparing for university entrance exams.

The appalling fact is that schools deliberately skipped some compulsory subjects. Behind this is entrance examination hell. In most cases, world history was sacrificed so that students would have more time to study subjects like English and mathematics, which feature prominently in the entrance exams. This practice has taken place mostly at so-called elite high schools, where many graduates go on to prestigious universities. Many schools have submitted falsified reports to prefectural boards of education.

Teachers at public high schools, which hold classes five days a week, in particular feel pressure because their students have to compete in university entrance exams with students from private high schools, which hold classes six days a week.