TX Nonprofit-Can Employee Volunteer

[MajorTH]

Nonprofit educational organization pays instructors to teach individualized 4-10 week educational courses multiple times throughout the calendar year between 8 am and 5 pm. Courses are offered spring, summer and fall. When the courses are not in session, their is no need for the instructor to work on the course and thus instructor is not paid. Can the instructor, if they desire and at no coercion from employer, volunteer for the educational organization between 8 am and 5 pm performing services that are NOT same as, similar or related to their paid instructional duties when they are not teaching and their courses are not in session? Instructor may teach January-March (paid time), off April-May (unpaid time), teach June-July (paid time), off August-October (unpaid time) and teach November-December (paid time).

I realize a full-time employee may not volunteer for non-profit in a role that is similar to their paid duties and more than likely may not volunteer during their normal work hours. Thus for the instructors listed above in an educational setting, what are normal work hours of these instructors and can they volunteer when they are not teaching?

Another factor to this question is the instructor is required to pay for employer provided housing and meals while they are a paid employee. If they move to volunteer status when courses are not in session, then organization would be give them free housing and meals. Does this change anything?