If you are done with an assignment and no longer want it cluttering your workspace, you can archive the assignment. Archiving the class will still give you access to it's assignment data, but it would sit in your workspace.
Step 1: From your class select the "Manage" dropdown menu, and click archive
Step 2: Select the assignments you would like to archive, and then click next
Step 3: The following message will appear in a pop-up. After reading the message, click archive.
The selected assignments are now hidden from your class. When you select the manage dropdown menu, you will see the number of archived assignments.
Select the "Manage" dropdown menu, and click unarchive. Then select the assignments you would like to bring back, and click unarchive.
Your assignments should not be visible by you and your students.