California Code, Education Code - EDC § 51423

(b) Notwithstanding any other law, the Superintendent may grant a waiver to a county office of education to provide a preparation program, for a high school equivalency test that has been approved by the state board, as part of any other instructional program during the regular schoolday to a person who is at least 17 years of age, has accumulated insufficient units of high school credit to graduate from high school by 18 years of age, and is confined to a state or county hospital or to an institution maintained by a state or county correctional agency.