St. Thomas Aquinas High School (STA) is a private, Catholic co-educational high school located in Louisville, Ohio, United States, run by the Roman Catholic Diocese of Youngstown. It was founded in 1964 to serve the Catholic families of eastern Stark County and parts of Portage County. When it opened, Aquinas enrolled both male and female students, but was a single-sex educational institution, as boys and girls attended classes within separate wings of the school. STA began practicing its current co-educational format in 1970.