This study examines three questions about the impact of collaboration during scientific argumentation. First, do groups craft better arguments than individuals? Second, to what degree do individuals adopt and internalize the arguments crafted by their group? Third, do individuals who work in groups learn more from their experiences than individuals who work on their own? To examine these questions, 168 high school chemistry students were randomly assigned, using a matched pair design to "collaborative" or "individual" argumentation conditions. Students in both treatment conditions first completed a task that required them to produce an argument articulating and justifying an explanation for a discrepant event. The students then completed mastery and transfer problems on their own. The results of this study indicate that (a) groups of students did not produce better arguments than students who worked alone, (b) a substantial proportion of the students adopted at least some elements of their group's argument, and (c) students from the collaborative condition demonstrated superior performance on the mastery and transfer problems. These observations indicate that collaboration was beneficial for individual learning but not for initial performance on the task. The study concludes with a discussion of these observations and recommendations for future research. (Contains 4 tables and 3 figures.)