High Quality Content by WIKIPEDIA articles! Mater Dei Catholic High School is a private, Roman Catholic high school in Chula Vista, California. It is located in the Roman Catholic Diocese of San Diego. Mater Dei Catholic replaced its former school, Marian Catholic High School, in September 2007. The rebuilding/renaming came as a result of the Diocese`s decision to upgrade all of its secondary campuses in the last five years. The original campus was located in South San Diego.