Sometimes, you don't need to read all of the Discussion threads and replies, but they are still listed as unread on your Brightspace page.  Just like marking emails as read, you can mark your Brightspace discussions as read to remove that notification icon.  To do this:

1. Go into the Discussions Tool. 

2. Then click on the name of the Topic to go into the Discussion Topic. 

3. Then click on the arrow to the right of the Topic Name to open the dropdown menu. 

4. Then click on the option Mark All Threads as Read.