Is it possible for students to view a list of modules, which are not published, to determine if there are any modules that they need to make up?
It is not possible. By definition, student's cannot see modules that are not published. I like to say "published" mean "invisible". That's not totally correct but in this case it is. The other thing to know is that if you put something else like an assignment in an unpublished module, that assignment will not be available to students even if it's published and linked to from somewhere else.
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