Southwestern Academy is a private, coed, college preparatory school founded in 1924. It is nonprofit and operates two campuses in San Marino, California and Rimrock, Arizona for students grades 6 to 12 and post graduates of high school preparing to attend college. Students attending either campus can transfer at any time to the other school as the classes are synchronized at both locations. It is accredited by WASC.

Southwestern Academy competes in the California Interscholastic Federation and Northern Arizona Sports Conference, fielding teams in soccer, cross country, basketball, baseball, volleyball, track and field, and golf. Its teams have won 77 championships since its founding and all students who try out for the teams are accepted. Many outdoor activities are available to students at the Arizona campus including horseback riding, camping, astronomy, fishing, and mountain biking.

The California campus is located on 8 acres in the suburbs of Los Angeles. Southwestern accepts 60% of its applicants and has a student body of 128 students. Tuition is $50,500 for international boarding students and $44,600 for domestic boarding students. The school’s mascot is the suns.