Student Access to Courses

Hi there, Once a student changes their membership option from a paid membership to a free basic membership option - is there a way in the admin area to see all the courses that they took to make sure they don't have access to the paid courses they were in?  (I have checked the activity section but know that they can delete their own activity section and I don't want to have to search 100 different courses to delete them from all the courses...) They still seem to have access to old paid courses that they took even though it is reserved only for paying members.  But because they were already in the course before they changed their membership status, the system doesn't kick them out of the course. Thank you!