From 1920 to 1961 our district was known as the Arlington Union Free School District, Number 7. When the district was formed, there were two school buildings, one on College Avenue and the other on Davis Avenue. At that time only one year of high school work was offered. In 1922 the course was expanded to two years, and in 1924 the district offered three years of high school work.

The Arlington High School was granted a charter as a six-year high school in 1926, and its first commencement was held in that year with nine pupils graduating. At that time classes were held in the building where the Arlington Grade School is now located.

In 1934 a new high school as erected near the junction of Routes 44 and 55, with additions being made in 1940 and 1953 to accommodate the increasing number of students. At the time of the latter addition a separate Junior High School was established in the north end of the building.

On July 1, 1951, the new Arlington Central School District #1 was formed. In 1959 the District voted to build a new high school at Freedom Plains. This building was occupied by Grades 10-12 in September 1961. In 1967, space to accommodate 500 more students was added making the present capacity 1500 students.

In 1979 the Arlington District was reorganized to accommodate a declining enrollment in elementary schools coupled with overcrowding in the high school. The former LaGrange Junior High School on Stringham Road became a part of the Arlington High School which is now a four year high school, Grades 9-12. The building on Route 55 was designated Arlington High School, North Campus and the former LaGrange Junior High was designated Arlington High School, South Campus.

The old high school building is now occupied by the Arlington Middle School Grades 6-8.

In September 1998 the new addition to Arlington High School opened allowing all 9-12 students to be situated on one site off route 55. The former South Campus on Stringham Road became Lagrange Middle School for grades 6-8. The former Titusville Middle School opened as Titusville Intermediate School for grades 3-5 and Overlook Elementary School became a K-2 center