This study investigated the impact of discussion forum design and facilitative strategies on student participation and cognitive levels of student dialogue. A multiple-case study design was used. Three online classes taught by the same instructor participated (n = 55). Data were collected from observations, discussion transcripts, and teacher interviews. Results from content analysis of the discussion transcripts showed that the teacher's role in online discussions is influential in student participation and learning. Instructional strategies such as participation requirements and question design were related to an increase in participation and cognitive levels of student dialogue.