Rio Mesa High School (RMHS) is a high school in Ventura County, California. Located northeast of Oxnard, the school is surrounded by strawberry fields and other crops growing on the Oxnard Plain. The school is part of the Oxnard Union High School District (OUHSD). It serves a portion of northeast Oxnard (including the neighborhood of RiverPark) and western Camarillo as well as the unincorporated communities of El Rio, Strickland, and Nyeland Acres. The name "Rio Mesa", conceived by OUHSD board member Bob Matthews at the time of the school's founding in 1965, is derived from the two original elementary school districts that fed the school — Rio and Mesa Union; since then, it has also regularly received students from the Pleasant Valley and Oxnard Elementary districts. Rio Mesa High School offers the International Baccalaureate Diploma Program.