In order to be effective teachers, we need to motivate our students, which means we need to know how they respond to incentives. Are they output-maximizers and early success encourages them to work harder for the greater reward? Or are they cost-minimizers and early success tells them they can put in less effort and still succeed? This paper presents the analytical results from new data available on students’ studying time on an online assessment website. Effort is tracked for one hundred sixty-eight students over the Fall 2010 and Spring 2011 semesters in order to better understand the relationship between grades and studying. The average student was a cost-minimizer.