Three voting behaviors and three types of volunteer participation were analyzed using longitudinal data from NELS:88/2000, a national sample of over 12,000 eighth graders in 1988 who were young adults in 2000. From 1994 to 2000 this cohort increased about 10% in both the three voting behaviors and the three volunteer participations. Wide race/ethnicity and smaller gender differences favoring females were observed both in voting behavior and volunteer participation. Higher socioeconomic status and higher student-reported middle school social studies grades predicted increased voting and volunteer participation. Each with one exception, regular high school diploma and years of education also predicted increased voting and volunteer participation. Higher scores on the 12th grade standardized test score predicted high voting patterns but presented a mixed pattern with the three types of volunteer participation. (Contains 4 tables and 2 notes.)