Here are notes from ITS and COLI administrators that are the result of our investigations or recorded observations about D2L and it's various features. The latest of these have not yet made it into our training videos, but will be included in the next replacement of the appropriate video.
...
In the below example, only students who score at or below 75% can take the quiz a second time:
Discussion Post History
You can see the history of your students' discussion posts in D2L. This includes revisions.
Changing Grade Value Denominator: Dropboxes and Grades
...