Big Walnut High School is a public high school located in Sunbury, Ohio. It is the only high school in the Big Walnut School District. The first Big Walnut High School to open was in August 1951 at 105 Baughman Street. The current building was opened in January 2022 to meet the demands of the growing district and has a student population of approximately 1300 students. The school's mascot is the Golden Eagle.