I actually don't believe that it is necessary to write this Idea, but here it goes:
Today I learned, completely by accident, that there is a limit to the courses that are shown on the dashboard. And it is completely intransparent to the user why they are not being shown all of their courses.
So, the solution is simple. Actually embrace good UX design principles and:
Change the amount of courses that are shown on the dashboard when a user hasn't starred any courses to show ALL courses.
Or, if you really can't, add an information prompt that actually notifies users that something is being filtered.