What is the collective noun for classes?

There isn't a widely accepted collective noun specifically for "classes." Here are some options you could use, depending on the context:

General:

* Group of classes: This is straightforward and always accurate.

* Set of classes: This implies a structured or organized collection.

* Curriculum: If you are referring to the entire body of classes offered by a school or institution.

More specific:

* Cohort: This is often used for a group of students taking a particular set of classes together.

* Schedule: This implies a planned arrangement of classes.

Ultimately, the best choice depends on the specific context and the meaning you want to convey.