As a reminder, state law (T.C.A. § 49-5-101) mandates that all teachers, principals (including assistant principals) and supervisors be properly licensed:

T.C.A. § 49-5-101.Basic requirements.

(a) No person shall be employed as principal, teacher or supervisor of any public elementary or high school by any local school district, or receive any pay for such services out of the public school funds of the local school district until the person presents to the director of schools a valid license as prescribed in this part. It is unlawful for any board of education to issue any warrant or check to such persons for services as principal, teacher or supervisor until the person has presented for record a license valid for the term of employment.

Securing and maintaining a valid teaching license is the responsibility of each individual teacher.