Originally built to function as a rural schoolhouse that is equipped with two rooms and can hold up to 110 students, the Mason District Number 5 Schoolhouse is one of the historic buildings in Mason Township, Michigan. It also served other functions, like as the mason Township Hall in 1964 and the Cass District Library?s Mason-Union Branch.

Built around the mid 1870s, the school house has been called the Kessington School House and the Sailor School. It was used as a school building until 1959, and in 1964, the Mason Township purchased the building to be their township hall. The Cass County Library was founded almost a decade later in 1973 in the hall and used the building to serve the members of the county.

Restored in 1984, the Mason District Number 5 Schoolhouse was declared a Michigan State Historic Site in 1980 and became a part of the National Register of Historic Places in 1985.