Currently, if there is attendance recorded for any section of a course, the schedule cannot be modified/class canceled for any other section, including those without attendance recorded. 

For example, if you have a French course, with sections 1, 2 and 3, and sections 1 and 2 have recorded attendance, section 3 cannot be modified/canceled until attendance for the other two sections has been cleared.

To clear attendance,a Schedule Manager can:
1. Navigate to onRecord.
2. Procedures > Section Attendance.
3. Filter for Status: Recorded | Group Type | School Level
4. To the right of each section of the course, click "Clear."

This will then allow you to back to the Master Schedule, and edit the schedule for the course, or cancel the section.