Just as a student has a To Do List and calendar of due dates in each of her/her courses, observers also have access to that information similarly.
From your Dashboard, on the right is a list of 'Coming Up' assignments for students you are assigned to:
You can also see more detail of the items by click on Calendar from the Global Navigation on the left:
Each course is color coded with due dates indicated on the calendar:
If you prefer to see this in list format, select the Agenda view at the top: