You can "group" assignments to make it easy to manage. Groups do not affect assignment publishing, grading, etc. Those attributes are set at the assignment or the part level.
Creating a group
Select "New Group" in the "Edit Assignment" page -
Enter the group name and select "Save and Continue"
The group should show up in the list on the left
Adding assignment to a group
You can have two options to add an assignment to a group. You can open the group and then dragging an assignment to it
You can also select an assignment and using the "Move to group" selection
Deleting a group
You can use the "trash can" symbol next to the group name to delete the group. NOTE: All the assignment in the group will also be deleted if you delete a group.