The chairperson of the board of land and natural resources is hereby requested, upon the recommendation and approval of the superintendent, to sell any state lands, including the buildings thereon, once used but no longer necessary for school purposes; provided that no school facility or portion of a school facility shall be sold before that facility or portion of the facility is made available for use by the department or charter schools, pursuant to sections 302A-1151.5 and 302D-24.