Any teacher who fails to comply with the provisions of his contract without the written consent of the school board shall be deemed guilty of unprofessional conduct. A breach of contract resulting from the execution of an employment contract with another board within the State without the consent of the board first employing the teacher makes void any subsequent contract with any other school district in South Carolina for the same employment period. Upon the formal complaint of the school board, substantiated by conclusive evidence, the State board shall suspend or revoke the teacher’s certificate, for a period not to exceed one calendar year. State education agencies in other states with reciprocal certification agreements shall be notified of the revocation of the certificate.