Your instructors may ask you to Submit pages from your ePortfolio; this is a method for archiving your Signature Assignments completed for the class. Go to Portfolio Tools > Submit, choose the course and follow the directions.
It is always a good idea to keep your own archive of your work. Get into the habit of making a backup of your entire ePortfolio each semester. Go to Portfolio Tools > Download and follow the directions.
For some modules, you can retrieve an auto save of the content. If you delete the module all of its content disappears forever. There is no way to retrieve a deleted module, page, section, or e-portfolio unless you have made a backup of it.