Class Conversations allow all members of a course to post and view discussion-style messages related to a specific document, test, or assignment...
Items with an unread conversation post (response) appear with a blue speech-bubble left of the item name in the Course Content list.
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To reply to a conversation post, click the REPLY button at the bottom of the post you wish to respond to.
Type your message, then...
You can allow class conversations (item-based discussion) on Document, Test, and Assignment item-types in Blackboard ultra-style course sites....
There are 3 ways you can access a class conversation.
From the Course Content list, click the "..." button right of the item...
From the Conversation page, click the box containing the prompt text "Type a response." Enter your message text and click the respond...