Deirdre,
Yes, allowing students read-only to their old classes will be an option. Actually, there are going to be two options : read only to students and read only to course admins. You would be able to 'expire the class for students', 'expire the class for course admins' or 'expire the course for everyone' (give read-only per each case).
About browsing by term: In the groups portlet (user portal) We will only show the current courses and will add a link to show all the 'expired courses' grouped/ordered by term. What do you think?
Thanks for your comments :).
