What do you know about Finland? That it is the happiest nation on earth? Correct. That the school system is superb? Well, half right. Finland does indeed always rank at or near the top of the international league table for educational outcomes – but that’s because of the girls. Every three years, the OECD conducts a survey of reading, mathematics, and science skills among 15-year-olds. It is called the Pisa (Programme for International Student Assessment) test, and it gets a lot of attention from policy makers. Finland is a good place to look at gender gaps in education because it is such a high-performing nation (indeed, one could say that other countries suffer from a bout of Finn envy every time the Pisa results are published).