The county board of education shall appoint, upon the written recommendation of the county superintendent, all principals, teachers, clerical and professional assistants authorized by the board. The county board may suspend or dismiss for immorality, misconduct in office, insubordination, incompetency or willful neglect of duty, or whenever, in the opinion of the board, the best interests of the school require it, superintendents, principals, teachers or any other employees or appointees of the board, subject to the provisions of Chapter 24 of this title.