1. Open the Student Overview in the Course Dashboard.
2. Mouse over the green buttons to find the lesson you want to unlock. The name of the lesson will appear as you hover. Select the appropriate lesson.
3. In the popup, select "Unlock Lesson."
The popup will ask you to confirm your selection.
4. The lesson's dot will now be gray and the student can resubmit their answers.
The student's answer entries should remain in the lesson, so they should review their answers and make any necessary changes before submitting the lesson again.