Open Settings

In Course Navigation, click the Settings link.
Open Course Details

Click the Course Details tab
Set Course Participation Dates

Click the Participation drop-down menu and select Course
Set End Date

To select the End Date, click the End calendar icon. Then select a new end date for the course.

If your End Date time is midnight, a warning message displays notifiying you that the date prior to the set End Date will be the last participation day in the course. For instance, if the course were set to end June 30, the last full participation date for the course would be June 29.
Update Course Details

Scroll to the bottom and click the Update Course Details button