The reversal is laid out in a report published on March 5th by the OECD, a Paris-based rich-country think-tank. Boys’ dominance just about endures in maths: at age 15 they are, on average, the equivalent of three months’ schooling ahead of girls. In science the results are fairly even. But in reading, where girls have been ahead for some time, a gulf has appeared. In all 64 countries and economies in the study, girls outperform boys. The average gap is equivalent to an extra year of schooling.
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To see why boys and girls fare so differently in the classroom, first look at what they do outside it. The average 15-year-old girl devotes five-and-a-half hours a week to homework, an hour more than the average boy, who spends more time playing video games and trawling the internet. Three-quarters of girls read for pleasure, compared with little more than half of boys. Reading rates are falling everywhere as screens draw eyes from pages, but boys are giving up faster. The OECD found that, among boys who do as much homework as the average girl, the gender gap in reading fell by nearly a quarter.