You may need to end a class to prevent the class from appearing in your plans.
To do this -
1. Click Go To -> Classes
2. Click on the class you wish to adjust
3. Adjust the end date of the class to a date of your choosing. Please note - you cannot choose an end date that is in the past and all existing lessons in the class after this end date will be deleted
4. Save the changes by clicking the checkmark in the upper-right corner of the screen