Can I delete the Course Buttons on the left-hand side?

1. You can change, delete, and rename the Menu buttons on the left hand side that are related to the Content Areas: Course Information, Course Documents, External Links, Assignments, you may do with as you wish. Configure these in the Control Panel > Manage Course Menu area.
2. You can change the color and style of the buttons in the Control Panel > Settings > Course Design > Course Design area.

WARNING! Do NOT delete the Announcements, Tools, Discussion Board, or Communications buttons, even if you don’t use them. Once you delete them it is very difficult and sometimes impossible to get them back.

How can I clean out an already existing course to reuse it?

1. Use the Control Panel > Recycle command which is specifically designed to let you clean out certain parts of a course that change from term to term, e.g. student accounts, discussion board entries, etc. This is a very useful command.
2. Note that it cleans out the course as it is, so the data you are cleaning out is gone forever. It is a very, very good idea to first Archive a course before Recycling it.