There are two ways that school districts can merge: school district annexation (MCA 20-6-422) and school district consolidation (MCA 20-6-423).
I've given you the Montana Code/Statute for these. You can find the full statutes for these two citations at: http://data.opi.mt.gov/bills/mca_toc/20_6_4.htm
Basically annexation is when a school district becomes part of another existing school district and takes on the identity of that school district. Consolidation is when two or more existing school districts merge together to form a new school district with a new identity made up of the former school districts. Annexations and consolidations can happen in two ways:
1) the school trustees pass a resolution requesting the County Superintendent to order an election to consider the annexation or consolidation (whichever the school trustees have passed in their resolution) for their school district, OR
2) at least 20% of the electors of the school district who are qualified to vote may petition the county superintendent requesting an election to consider annexation or consolidation (whichever they have specified) for their district.
The Montana Legislature can change the law or implement a law directing consolidations or annexations, but they have not attempted this as it would be contrary to local control. No other entity has the ability to direct an annexation or consolidation. In other words, the State Superintendent, the Board of Public Education (policy making board for K-12), the Governor, etc. could not order school consolidation or annexation.
In the 1969-70 school year there were 781 school districts. Thirty-eight years later in 2006-07, last school year, there were 433 school districts, with a decrease in the last 18 years of 112 school districts. The decrease has been due to a variety of things, including annexations, consolidations, school districts that have gone into non-operating status due to no students, and a statute passed by the 1991 Legislature that directed elementary and high school districts with exactly the same boundaries to form K-12 school districts (impacted 110 school districts that became 55 K-12 districts).
For further information and assistance please contact Nica Merala at OPI -- 444-4401
5th of February, 2010