Whether argumentation competencies are associated with the kind of influence opportunities children have in their lives is the focus of this study. The hypothesis is that when children have the opportunity to initiate and evaluate arguments, hear others make and examine arguments, and participate equally in resolving disputes, children are able to develop their argument skills. Four argumentation competencies associated with critical discussions of proposals are identified: creating consensus about problematic situations, advocating proposals, facilitating behavioral commitment, and integrating identities. Second, (...) fourth, and sixth grade children completed tasks that assessed their influence opportunities and argument competencies. Children who perceived themselves to have many collaborative influence opportunities, that is, opportunities in which they could engage in mutual influence, had more highly developed argument competencies than children who did not have such opportunities. As predicted, this relationship occurred with the argument competencies of problem conception, proposal advocacy and facilitating commitment. Measures of non-collaborative influence opportunities were not associated with argument competencies. Together, the results suggest that discussions in which children are given the opportunity to influence and be influenced with arguments may provide the best context for children to develop their argument skills. (shrink)