When the option 'Large course: Launch SpeedGrader Filtered by Student Group' is selected, you cannot change the group you are grading inside the Speedgrader. This confuses teachers.

Right now if a teacher would want to change the group they are grading the workflow is as follows:  close the Speedgrader, select a different group on the assignment page (or in the Gradebook) and reopen the Speedgrader.

The proposed solutions would be to add a dropdown menu (like the filter by section option in the Speedgrader) to change the group, without having to exit the Speedgrader.