Headquartered in sunny Pasadena, the Caltech Science Olympiad Club serves to organize and support many Science Olympiad events in Southern California. The annual SoCal State Tournament, which brings together over 2,000 students, teachers, and coaches on Caltech's very own campus, has been hosted here since 2016, and the Summer Coach's Workshop has been at Caltech for even longer. The club consists of both undergraduate and graduate students - if you are at Caltech and interested in helping out with Science Olympiad, please don't hesitate to reach out!

The Caltech Science Olympiad Alumni Chapter started in 2004 with just a couple of volunteers looking to give back to Science Olympiad. This was the start of the Science Olympiad alumni effort that started on the West Coast that took place at the same time as when Yale Science Olympiad started their alumni chapter. The Caltech Science Olympiad Club served as test writers and event supervisors for the Los Angeles Regional Tournament and the Southern California State Tournament. Over time, the Caltech Science Olympiad club took on a bigger role with the local tournaments and organized the LA Regional and SoCal State Tournament in partnership with the Regional and State Directors. At the same time, members of the Caltech Science Olympiad Alumni Chapter worked with colleagues at MIT, UCLA, Duke and other universities to help them start their own alumni chapters.