LIFE for Indian women is hard. According to a survey of experts in women’s rights by Thomson Reuters, the prevalence of rape, human trafficking and forced marriage make India the world’s most dangerous country for women. Among G20 members, only Saudi Arabia has a lower rate of female participation in the labour market. Moreover, the share of Indian women who have jobs in the formal or informal economy has actually fallen in recent years, from 35% in 2005 to 26% today. Such discrimination inflicts a large economic cost. The IMF reckons the country would be 27% richer if as many women worked as men.

How can India solve this problem? Simply educating more girls might not help. Whereas poor, illiterate women have little choice but to work, those with secondary schooling tend to marry into families of higher social standing, who insist that they look after the children. Husbands frequently think that job-seeking wives are a mark of shame.

Any solution to India’s gender gap must tackle that stigma. Getting men to do more housework is crucial. Women currently contribute six of the seven hours required each day. Data from the OECD suggest that husbands and sons chipping in an extra hour could increase the female workforce by five percentage points.

Changing the attitudes of India’s 700m men will be tricky. But a working paper by Diva Dhar, Tarun Jain and Seema Jayachandran shows that it is possible. The three economists have studied the effects of a programme organised by Breakthrough, a non-profit, that gave lessons about gender stereotypes to 11- to 13-year-olds. The programme was randomly allocated to 150 schools in Haryana, a northern state where gender discrimination is particularly stark. Its teachers, who were mostly male, led 27 classroom sessions over three years, which focused on economic and human-rights arguments for treating women fairly.

The intervention seems to have worked. Compared with teenagers at nearby schools, those who had participated in the programme were much less likely to agree that women ought to be housewives, and that men should get the final say on decisions. The impact was similarly large for students with socially conservative parents and those with progressive ones.

The economists also surveyed students about whether they had helped with chores in the past week. These effects were smaller, but still statistically significant. Boys at participating schools were nearly five percentage points more likely to have contributed to cooking and cleaning than those who had not taken the gender-discussion classes. Girls also became more likely to help out with shopping, which is usually reserved for men. The clearest change was an increased comfort in speaking to the opposite sex, among both boys and girls. If the lot of Indian women is ever to improve, the men will have to start listening.