Reorganization of school districts may be accomplished through or by means of any one or more of the following methods: (1) The creation of new districts; (2) the uniting of one or more established districts; (3) the subdivision of one or more established districts; (4) the transfer and attachment to an established district of a part of the territory of one or more districts; and (5) the dissolution or disorganization of an established district for any of the reasons specified by law.