[4] The school opened in January 1959, initially with freshman and sophomore students only,[5] adding juniors in the fall and its first senior class in September 1960.

[6] Senator Robert F. Kennedy spoke at a student-organized mock Democratic Convention held at Sunset High School on May 17, 1968, less than three weeks before his assassination on June 5.

[7][8][9] Sunset High School is located in the predominantly unincorporated area known as Cedar Mill.

From 1959 to 1999, the school property was unincorporated land in Washington County, with it being in the Cedar Mill census-designated place as of the 1990 U.S.

[11] In 1999 the Sunset High School grounds (including the adjacent swimming pool) were annexed by the city of Beaverton.