The Dialectical Map (DMap) is an open-source, web-based argument visualization tool developed and used at a Canadian University to scaffold argument construction. To illustrate the ways that argument mapping can be used in undergraduate courses, this article presents five cases selected from courses in biology, psychology, computing science, and English as a foreign language offered at three post-secondary institutions. Each case explains how argument mapping with DMaps (DMapping) was implemented and assessed in a course. Students responded to a questionnaire that gathered their attitudes toward DMapping as a learning activity. In each course, students were also interviewed about their DMapping experiences. The interview and questionnaire data indicated that students believed DMapping was an effective way to meet the knowledge objectives of their course and to learn about argumentation. The authors explain how DMap assignments added value to their courses by helping students think critically about course topics while developing their argumentation ability and information literacy. Finally, we summarize the lessons learned across the cases and discuss ways of maximizing the benefits of argument mapping activities for postsecondary learning.