Online discussions have been increasingly integrated into face-to-face classes at universities to enhance student learning of course content. The primary focus of past research has been on the end products of online discussions. Studies reported either successful findings or results that fell short of desired learning outcomes. An in-depth investigation is needed about how the design of online discussions is related to success. This paper reports our experiences in conducting a three-phase, design-based study: (1) designing the online discussion activity; (2) implementing our design in a university course; (3) empirically investigating our design. (Contains 4 tables and 3 figures.)