(a) Local school boards are hereby authorized, pursuant to rules and regulations established by the State Board of Education, to employ provisionally certified persons from business, industry or other areas or military retirees who have extensive preparation in mathematics, science, computer education and other critical needs areas for a period not to exceed one year with a limit of three years total employment. Such persons may be employed provided:
(1) They have at least a bachelor's degree in subject they are assigned to teach;
(2) There are no regularly certified teachers available to teach the course to be taught by these persons; and
(3) They are evaluated regularly and offered proper guidance by their supervisors.
(b) The time served as a provisionally certified teacher under this section shall not count toward time earned for tenure.
(c) The employment of provisionally certified teachers under this section shall serve to supply an emergency source of teachers in critical needs areas and shall not be considered a permanent means of acquiring teachers in any area.