The rates of increase in school population in Minnesota and population shifts and economic changes in recent years, and anticipated in future years, have required and will require large expenditures for performing the duty of the state and its subdivisions to provide a general and uniform system of public schools. The state policy has been to require these school costs to be borne primarily by the local subdivisions. In most instances the local subdivisions have been, and will be, able to provide the required funds by local taxation as supplemented by the aids usually given to all districts from state income tax and other state aids. There are, however, exceptional cases due to local conditions not found in most other districts where, either temporarily or over a considerable period of years, the costs will exceed the maximum which the local taxpayers can be reasonably expected to bear. In some districts having bonds of several issues outstanding, debt service tax levy requirements are excessive for some years because of heavy bond principal payments accumulating in some of the years due to overlapping or short term issues. The policy and purpose of sections 126C.61 to 126C.72 is to utilize the credit of the state, to a limited degree, to relieve those school districts, but only those, where the maximum effort by the district is inadequate to provide the necessary money. It is also the purpose of sections 126C.61 to 126C.72 to promote efficient use of school buildings. To that end, a district that receives a maximum effort loan is encouraged to design and use its facility to integrate social services and library services.