Morocco is one of the more developed countries in Africa, but only about half -- 56 percent -- of its population can read. Most schools there lack electricity, and many don't even have toilets. Most children living in the country's rural areas start primary school, but about 40 percent drop out before sixth grade. The rudimentary education system makes its mark in the country's test scores: It's ranked 59 out of 69 countries in math and 64 out of 70 on science.
To nudge families to keep their children in school, researchers recently experimented with giving parents in the country's poorest districts small grants of between $8 and $10 per child each month. Some of them were told they'd only get paid if their child attended school regularly, but the others were simply handed money, told nothing, and sent on their way.