Peer discussions of differing ideas enhance conceptual understanding. Applying this to college STEM courses presents challenges like short class times, large sizes, and a competitive culture. To address these, I developed CONSIDER (CONflicting Student Ideas Discussed, Evaluated, and Resolved), a web-based collaborative learning approach. It features structured, anonymous discussions where students address conflicting ideas in small groups. Evaluated across three undergraduate courses, CONSIDER showed improved learning and participation compared to an unstructured forum-based approach in two studies. While one study showed no significant difference, most students preferred the structured, anonymous format for its impact on learning and engagement.