Students work on a classroom exercise at a school in Kibera, a poor neighborhood in Nairobi, Kenya. A new study finds that girl-centric programs may not be the only effective way to boost girls' school performance in low-income countries. You'd think the best way to get girls to succeed in school would to be design programs specifically for them — offer them mental health support or free menstrual pads. World Bank Economic Review, begs to differ. Researchers David Evans and Fei Yuan reviewed 267 studies of education programs from 54 low- and middle-income countries to find the most effective ways to get more girls in school and improve their learning. Globally, more than 130 million girls remain out of school, according to the World Bank, due to poverty, child marriage and violence.