The unit tests cover this quite well, but ... 1. Set up a quiz so that students are not allowed to review anything. 2. Get a quiz attempt into the never submitted state. (When time expires -> Attempts must be submitted before time expires, and set a time limit. Start a quiz attempt as a student. Log out. Wait until time has expired. Log back in, and try to access the quiz attempt.) 3. Ensure that the student cannot review the attempt.