Mary,
We're using 2.6.3+ and I can't replicate your experiment precisely. I think I have read all the posts on this confusing topic and I have come to the conclusion that:
- "Group submission settings" are "Collaborative assignment settings". Here you specify the grouping that contains the groups for the assignment.
- "Common module settings" affect the visibility/availability of items.
For non-group assignments this only affects how items are shown to teachers for grading (all in one list or in separate lists for each group). If teachers are included in a group and the teacher permissions are modified at the course level so that they can only see groups they are in, then that will happen.
For group assignments, the effect on grading for teachers is the same as above. For students, in the case of group assignments, you don't need to set up anything special. You can have Group mode: No groups; Grouping: None; Available for group members only: Unchecked. Changing these settings will only change the way the teachers have access to the different groups for grading purposes.
But don't set a different grouping from in the "Group submission settings" and check the availability only box. This could hide the activity from the very students you want to be able to do it!- Group mode: Only affects the grading view. If in doubt, use No groups.
- Grouping: You don't need to set up a grouping here unless you want to hide the assignment from some students. But usually your grouping in the "Group submission settings" will include all students anyway.
- Available for group members only: If you don't set up a grouping in the previous field this checkbox is irrelevant. If you set up a grouping there, you can use this box to hide the assignment from students not in the grouping. (I have read that this option has disappeared from the latest versions of Moodle, where it is now subsumed into the conditional activity architecture.) If you do not check this box, students who are not in the grouping in the previous field will see the assignment too.
- Apart from all the above, it is a good idea to set the course settings to Separate groups or Visible groups. Otherwise, students will not be able to see who else is in their group.
Well, I know that this is all fairly moot because we are using an old version of Moodle.
It certainly is complicated!