An Act amending the act of March 10, 1949 (P.L.30, No.14), known as the Public School Code of 1949, in grounds and buildings, further providing for referendum or public hearing required prior to construction or lease; and, in reimbursements by Commonwealth and between school districts, further providing for approved reimbursable rental for leases hereafter approved and approved reimbursable sinking fund charges on indebtedness.