(a) A teacher, including a teacher who has acquired tenure rights, may be dismissed at any time only for the following causes:

1. (1) incompetency, which is defined as the inability or the unintentional or intentional failure to perform the teacher's customary teaching duties in a satisfactory manner;
2. (2) immorality, which is defined as the commission of an act that, under the laws of the state, constitutes a crime involving moral turpitude; or
3. (3) substantial noncompliance with the school laws of the state, the regulations or bylaws of the department, the bylaws of the district, or the written rules of the superintendent.