Most of my research deals with conditional cash transfer programs in Latin America. These programs pay households if their children go to school and the family goes to health clinics. In the ones I have studied these incentives increase school enrollment between 5-20% and do all sorts of other great things.
The programs have worked so well that New York City has adopted them (link). However, New York city has added an extra wrinkle. In the US most kids go to school, but many do not achieve what they should. So Ronald Fryer, a Harvard Economist, helped design a program that paid kids money if they passed tests. Seems like the kids are liking the rewards according to this New York Times article.
Dr. Fryer has an interesting story in his own right from juvenile delinquent to Harvard professor in about 10 years.
Baltimore is giving the pay to pass option a chance too (link).
It is too early to tell if these programs in New York and Baltimore have worked as well as the conditional cash transfer programs, but it is worth a shot.
One final thought, the reason the successes of programs in Latin America has been so clear is they have been run as experiments, where half of children receive the program and half don’t (usually separated by communities).