Brightspace allows the user to Pin/Unpin courses to the dashboard. Pinning a course puts it at the top of the course list, and helps the user quickly access their frequently used courses. Unpinning a course will remove it from the dashboard, and keeps it hidden.
You can view all of your courses by clicking View All Courses after your pinned course icons.
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I need to know how to repin it back on my board not hide it
Go to your waffle and click on the empty pin icon.