Along the same lines what Bob wrote above: Is it a problem if the students not only see their grades but also see the content once the course is over? In my field it is the opposite. A foundational subject done in the first semester could be relevant even in the eight semester (or hopefully after graduation too).
Of course active participation in a finished course is not welcome. That needs to be blocked at the Activities level, using features like Common_module_settings#Availability, Restrict_access_settings.
Of course active participation in a finished course is not welcome. That needs to be blocked at the Activities level, using features like Common_module_settings#Availability, Restrict_access_settings.