Studied the relation between college grades and self-reported amount of effort in 4 major and several minor investigations of over 875 undergraduates in a large state university. Grades were operationalized mainly by using GPA, although in 1 investigation, grades in a particular course were the focus. Effort was measured in several ways, ranging from Ss' estimates of typical study over the term to reports of study on specific days. Despite reliability and validity data indicating that these self-reports provided meaningful estimates of actual studying, there was at best only a small relation between the amount of studying and grades, as compared to the considerably stronger and more monotonic relations between grades and both aptitude measures and self-reported class attendance. The assumption that college grades generally reflect student effort was not supported. This raises a larger question about the extent to which rewards are linked to effort in other areas of life–a connection often assumed but seldom investigated. (19 ref) (PsycINFO Database Record (c) 2007 APA, all rights reserved)