Q. How do I store files or folders in my online course area, for use in classes?

I recommend finding at least two different secure areas to store files/folders.  In each online course, at the home page, there is a toolkit section near the bottom.  Click on "files."  You can store your work in individual files for each of your classes.  This is then available to you wherever you have Internet access.  It is also standard to back up your files on a flash drive or on your individual student file on your school's secure server.