Unraveling the complexity of the increase in college grades from the mid-1980s to the mid-1990s

To determine the factors contributing to the widely reported increase in av erage undergraduate grades, data were analyzed from students from two diffe rent time periods: 22,792 students in the mid-1980s and 29,464 in the mid-1 990s. After controlling for student background characteristics and institut ional characteristics, it appears that undergraduate grades increased acros s different types of institutions and major fields, but the increases were not of the same magnitude or due to the same factors. Evidence of grade inf lation was found only at research universities and selective liberal arts c olleges, while grade deflation occurred at general liberal arts colleges an d comprehensive colleges and universities and in the humanities and social sciences. Also contributing to the increase in grades were changes in stude nt characteristics and subtle adjustments in grading reward structures at a ll institutional types and for all major field clusters In general, grading reward structures favored White students female students, and upper-divisi on students. Equally important, students' academic effort was rewarded cons istently across time at all institutions and major fields, with students wh o invested more time and effort in their studies reporting higher grades.