Service-learning evaluation rarely compares different cohorts of students, so it is difficult to determine whether the findings are reliable. This study compared attitudinal change in five successive cohorts of intergenerational service-learning students (n =59) enrolled in an introductory gerontology course at a major Midwestern university. Quantitative and qualitative data were used to investigate the attitudes of students. Results indicated that only Cohorts 1 and 2 showed significant positive change at posttest in overall attitude toward the elderly. Additionally, only Cohort 1 showed significant positive change at posttest in overall attitude toward working with elders and on an "I fear getting really old" item. Content analysis of open-ended questions indicated that Cohort 1 had the highest proportion of students with positive attitudes toward their own aging at the end of the service-learning. Possible explanations for these findings and implications for evaluation of intergenerational service-learning programs are discussed.