Select all students
Select "Delete student." This will clear their account so that they are able to sign up to their new school next year with the same username.
Rename or delete your class
NOTE: If you delete your class, you will also delete all of your settings (bonuses, jobs, store items etc.)! If you think you would like to keep your settings, we recommend keeping the class. If you want to delete the class but keep your settings you can always copy your settings over to the new class before deleting the original class!