The school added a new grade level each year, and Canyon del Oro High School was established and declared a high school by the State of Arizona on July 1,1965, serving grades 9-10 with only a few hundred students.
The school added a new grade level each year, and Canyon del Oro High School was established in the fall of 1964 with a ninth grade class. CDO was formally declared a high school by the State of Arizona on July 1,1965, serving grades 9-10, with only a few hundred students.