Mont. Code § 20-6-605
Whenever the trustees acquire land by deed conditioned upon the use of the land for the conduct of school or related activities or whenever land has been used by the trustees at the will or sufferance of the land's owner or claimant and the district has constructed buildings or made other improvements on the land, the owner or claimant may repossess the land if it ceases to be used as specified by deed or, if not specified, for the conduct of school or related activities. However, the owner or claimant shall first notify the trustees in writing of the intent to repossess the land, and the trustees shall have 1 year after receipt to remove any buildings or improvements placed upon the land by the district. The trustees' failure to remove the buildings or improvements within that time constitutes a forfeiture of the buildings or improvements. Before the owner or claimant has the right to give notice of repossession, the district's intention to permanently cease using the land must have been established by resolution of the trustees and a vote of the district's electors.
§ 20-6-605, MCA