This study explored what instructors can do to improve student depth of thinking in online discussion boards (DBs). Participants were graduate students enrolled in online courses within a college of education in the southwest United States. Measurement consisted of discourse analysis of posts in DBs and student self-assessment of dispositions, understandings, and practices. Analysis revealed extended posts correlated significantly to higher order convergent and divergent thinking. Less extended posts correlated significantly to lower level organization of threads. A disposition toward collaboration/reflection correlated significantly to exploration/ problem resolution. Evidence suggests instructors can influence depth of thinking by making expectations for depth of posts explicit.