The original 1885 campus on Jackson was closed in 2003 due to the aftereffects of multiple disasters (fires and earthquakes) and the inability to effectively repair the damage.

Pioneer Memorial Stadium, adjacent to the 1885 campus, continues as the OCHS venue for football, soccer, lacrosse, and track and field.

[citation needed] The OC Master Choir performed the song "Raua Needmine" (Curse Upon Iron) by the Estonian composer Veljo Tormis in the 2009 school year.

During the 2004–2005 school year, a political cartoon drawn by a student concerning the border issue between Mexico and the United States, was taken out of context, making national news.

During the 2016–2017 school year, a Twitter post that showed a group of students holding a sign that included a racial slur was released, stirring controversy.