High Quality Content by WIKIPEDIA articles! Valencia High School is a public secondary school located in the Santa Clarita, California community of Valencia, California, and part of the William S. Hart Union High School District. Valencia High School is known for outstanding academics, award winning fine arts / extracurricular programs, excellent student activities, and nationally recognized athletic teams. Valencia High Schools mission is to prepare students to meet the challenges of the future and to become responsible citizens through relevant learning opportunities, community involvement, innovative technology, and teamwork.