From the lessons module, click the Assigned radio button to view all assigned assessments for all your classes. You can narrow down to individual classes below the radio button.
To view your students' individual progress on lesson modules, hover over the lesson in the class you wish to view and click View Progress.
To change the due date or order lock, click the ellipses next to View Progress, then click Settings.
You can completely unassign the lesson, or unassign it from individual students by clicking Unassign or Manage Assignees.
When managing assignees, just uncheck any student that you'd like to remove from the lesson, and click Back.