The purpose of this study was to examine the importance of cooperative incentives and heterogeneous grouping as elements of cooperative learning in a college life science course. Cooperative learning may be defined as a classroom learning environment in which students work together in heterogeneous groups toward completion of some task. Cooperative incentive structures provide some type of group reward based on group products or individual learning. In heterogeneous grouping, students are arranged in order to maximize variety within groups. A 2 × 2 design was utilized in this study. The independent variables considered included (a) use of cooperative incentives in learning groups, and (b) use of heterogeneous grouping in cooperative learning groups. Dependent variables for all treatment groups were scores from a multiple-choice instrument developed for an earlier, related study, along with direct observational data on frequency of cooperative interactions. Analysis of covariance (ANCOVA) was used as the data analysis procedure for the achievement portion of the study, and analysis of variance (ANOVA) was used for analysis of the cooperative interaction portion of the study. No significant differences were found between the treatment groups.