What are module sets?
A module set is a collection of modules. This is an advanced feature that allows you to add an extra layer of structure to your course.
You can set up multiple module sets from the Course Setup > Content page.
You can display your module sets on the side-bar navigation. Clicking on a module set from the sidebar nav will open a pop-out menu displaying all the modules in the set.
Go to Course Setup > Appearance to add module sets to the navigation.