In 1824 a schoolhouse of hewn logs was erected near where the Methodist Church now stands. On the Ohio side of the village the first school building was also a log structure and stood in the extreme southwest corner of Preble County. The second Ohio building was a one-room brick schoolhouse and stood facing east on the Butler County side, along the county line. A third building was a two-story brick one, constructed in 1870, and was known in later years as the Stephens and Stewart Contracting Firm. About the year 1883 a two-room schoolhouse was built one mile west of the Indiana-Ohio state line on Route 27, serving the Indiana side of the village.

For about twenty-five years attempts were made to bring about a union of the two schools in the village. In 1893 school authorities and village citizens realized that both state schools were inadequate to meet the educational needs of the community and that a union of the two schools would be an answer to the local school problems. The Attorney Generals of both states were contacted, along with state school officials, and upon the opinions of these authorities, a special Union School District was created.

In 1893 the two states constructed the first Union School, placing the structure half in Ohio and half in Indiana. This first school consisted of seven rooms with an office and a basement. The school was operated by a school board of three men from the Ohio side of the village and three men. from the Indiana side. Mr. E. P. Wilson served as Superintendent and Mr. Grant Smith as the principal of the new school.

For many years the two boards continued to function as one, operating together, until the Indiana side of the village consolidated with the whole of Union Township in Union County, Indiana. The Ohio side of the village consolidated with a part of Israel Township in Preble County, Ohio and Butler County, Ohio.

In order to consolidate the school on this basis with the outlying districts, special legislation was passed by the general assemblies in both Ohio and Indiana in 1921. At this time the Indiana side of the school was placed under the jurisdiction of the trustee of Union Township, and the Ohio side of the school was operated by a five-member board, elected by a vote of the Ohio residents of the special College Corner, Ohio school district.

In 1925 a contract was let to the Woods Construction Company of Lima, Ohio for the construction of the present school building at a cost of $108,000. The building was dedicated on December 21, 1926. Mr. William McMahan was the superintendent of the new school, and Mr. Virgil Miller was the principal. The old building was torn down in 1927.

Students from the Billingsville School were brought into Union School in September of 1953. Bath Township in Franklin County, Indiana was consolidated into Union School in 1957, and the Union School Corporation was formed.

The first class to graduate from Union School was 1897 with eight members. The last class was in 1972 when it consolidated with the high school at Liberty and became known as Union County High School.