Trinity Catholic High School is the only co-educational Catholic high school in North St. Louis County. Our welcoming and caring community is committed to graduating responsible Christian citizens, dedicated to serving others and engaged in life long learning. Christ is the reason for this school. He is the unseen but ever present teacher in its classrooms. He is the model for its faculty and the inspiration for its students. Founded on the proud traditions of Mercy, St. Thomas Aquinas, Rosary, and St. Thomas Aquinas-Mercy High Schools, Trinity Catholic is a faith-based high school serving North County and the surrounding areas.