Individual semester-by-semester undergraduate grade point average for each of the eight semesters of the collegiate academic life cycle for five entire student cohorts for the classes of 1998, 1999, 2000, 2001, and 2002 at a large, private university in the northeast (N = 12,663) reveal a "check-mark" pattern: students' grades fell in the second semester, rose thereafter, and slumped in the last academic term. Attrition and participation in the Greek system explain over half of the longitudinal change in academic achievement. A comparison of the five cohorts of students indicates a rate of grade inflation comparable to that obtained for multischool studies covering the period 1960 to the late 1990s.