Class categories differ based on each teacher's preference for which categories they would like to add for their class. Administrators/teachers of classes have the option of customizing the toolbar on the left hand side. For example, some teachers like to have the assignments, discussions, and assessments tab, while some teachers only want to keep the modules tab.
Class categories that include Assignments, Discussions, and Assessments Tab because this teacher has these as their preferences.
Class categories that do not include Assignments, Discussions, and Assessments Tab because this teacher does not have these added to their preference.
