Glad to be of help Whitney...
You can tell if the student completion tracking is on by the fact that activities show up with one of 2 ticks beside it. A solid boxed tick means the student can say "I've completed this..." that's the default for the activity too. While a dashed box means certain criteria have to be met to complete e.g viewed, submitted etc. forums can even be set with a min number of posts. The 3rd option is to turn it off for the activity so it's not recorded. Once on though you can then use completion tracking in the conditional access. If you're the admin then you can turn on completion tracking in the Settings->Site admin->Advanced Features, then it's enabled for each activity individually.
In my case I'm trying to use it with a badge system I'm trying to construct (2.4.5 doesn't really support badges and I don't want to change to 2.5 or 2.6 yet as I changed up from 1.9 last summer. These badges are also totally in house so means nothing outside).
The badge link is invisible until the student "completes" the work, then they get the link and get awarded the badge when they click the link, it opens a popup that inserts their student ID, course ID and badge ID into a DB table while displaying the badge itself. The table is then read by some more php code at the top of the course page that fills out a "medal box" table showing the badges they've collected for the course, like the openbadges backpack but entirely in the course.
Works quite well, but it needs a lot before I can think of trying to foist it onto the teachers.