Dropping University Courses and Getting Paid for Grades

Students doing poorly in courses often consider dropping the courses. Many universities will offer a refund before a certain date. Should this affect a student's drop decision?

Children in poor neighborhoods have bleak outlooks on life and do not see much gain to studying. A recent experiment is paying children in poor neighborhoods $100 for each "A" they earn in a six-week grade reporting cycle. How does this affect behavior? Note include at least two reference.