In the city of Greensboro, N.C., there’s a program designed for teenage mothers. To prevent these teens from having another child, the city offers each of them $1 a day for every day they are not pregnant. It turns out that the psychological power of that small daily payment is huge. A single dollar a day is enough to push the rate of teen pregnancy down, saving all the incredible costs — human and financial — that go with teen parenting.
Most of the article focuses on “economics,” but of course money is only a context for the decisions they discuss.