When questions are posed to students for response, there must be guidelines.
1) THree or more original posts that answer the initial questions.
2) Three or four posts, responding to a classmate.
3) Redirect students back to the original questions, if they go off
on a tangent.
4) Instructor should guide students to explore the topic, in depth.
5) Students should learn more through the discussion, by writing
a "conclusion" posting.
You must also watch out for "plagaiarism" in the threads as well.