Use open-ended questions targeted toward higher-order thinking skills.In successful discussion boards, all participants learn from and teach one another. In order to support a deep and meaningful conversation, your initial discussion questions need to be interesting – perhaps even controversial – and allow for multiple perspectives that your students can provide from their own experience.
While I don't always like required response to each other's posts, I must admit I learn so much from my classmates posts in the discussion forums. A lot of the learnings come from group collaboration that were shared in the forum.