A minor bug. The Moodle Forum module has a "Default setting for 'Notify Students'" setting with a dropdown for "Yes" or "No". This does not appear in the default settings for the module in the site. When I save the setting as "yes" at the course level and re-enter the settings it is always still set to "No". I have done this in separate courses and tried creating a forum from scratch with the setting as "yes" but it always saves as "No".

Steps: 

1. Create a new forum module
   1. Forum type: "Standard forum for general use"
   2. Enable due date
   3. Whole forum grading.
      1.  Type: Point
      2. Grading method: simple direct grading OR rubric
      3. Default setting for 'Notify Students': Yes
   4. Save
2. Return to the forum settings and see that Default setting for 'Notify Students' is set to "No".