Founded in 1891,[1] it changed location several times in its early years before settling into its present campus at 601 Pico Boulevard.

In 1921, the Open Air Memorial Theater, now called the Greek Amphitheatre, was built to honor the Santa Monicans who served in World War I.

One of the best examples of the classical Greek style in Southern California, the amphitheater was built after Santa Monica passed a $30,000 bond measure to fund its construction.

In 1952, Santa Monica High School was finally expanded to what it is now, 33 acres (130,000 m2), and two new buildings were built, the Science and Technology D.M.

As the school aged, renovations took place in Barnum Hall and the Music Building was completely rebuilt.

The Innovation Building was constructed along with an outdoor gathering space called the Centennial Plaza and was ready by the start of the 2015–16 school year.

[4] The Discovery Building, including a new pool and cafeteria, was constructed and ready by the start of the 2021–22 school year.

[15] In 2016, the Wind Ensemble was selected to perform at the California All-State Music Educator's Conference (CASMEC) in San Jose.

[16] Girls Varsity team won the 2010 CIF Southern Division 1 championship, defeating Summit High, 69–63.

Boys Varsity won the 2013 CIF Division 1A Southern Section Championship against El Toro High School 66–56 at the Anaheim Convention Center.

[17][18] They also made it to the finals of the 2010 CIF Southern Division 1 Championship, but they were defeated at the Honda Center against Luezinger, and they went on to lose in second round of state.