The Grossmont Union High School District (GUHSD) is a public school district located in eastern San Diego County, California, and serves high school, adult school, and Regional Occupational Program (ROP) students in the cities of El Cajon, La Mesa, Lemon Grove, and Santee; and the unincorporated communities of Alpine, Casa de Oro, Crest, Dehesa, Dulzura, Jamul, Lakeside, Mount Helix, Rancho San Diego, and Spring Valley.