The State Board of Education shall be composed of eight members, who shall be elected from eight districts of substantially equal population as provided by the Legislature. Their term of office shall be for four years each. Their duties and powers shall be prescribed by the Legislature, and they shall receive no compensation, but shall be reimbursed their actual expense incurred in the performance of their duties. The members of the State Board of Education shall not be actively engaged in the educational profession and they shall be elected on a nonpartisan ballot.