California Code, Education Code - EDC § 49040

(a) The last two full weeks in April and the last two full weeks in September shall be known as “high school voter education weeks,” during which time persons authorized by the county elections official shall be allowed to register students and school personnel on any high school campus in areas designated by the administrator of the high school, or his or her designee, which are reasonably accessible to all students.

(b) This section does not preclude a person from registering to vote students and school personnel on a high school campus as is otherwise permitted by the Elections Code.