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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You can allow class conversations (item-based discussion) on Document, Test, and Assignment item-types in Blackboard ultra-style course sites....
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...
From the Conversation page, click the box containing the prompt text "Type a response." Enter your message text and click the respond...
There are 3 ways you can access a class conversation.
From the Course Content list, click the "..." button right of the item...