Sec. 9. TRANSPORTATION. It shall be the duty of any school district into which the county shall be subdivided under this Act to provide adequate and convenient means of transportation to and from the schools of such school children in any district as it may be reasonably necessary to make such provision for, and to establish such routes for that purpose as the Board of Trustees of such district may deem advisable and to alter and change the same from time to time and the expense of such transportation shall be paid by the district in which such children may reside.