California Code, Education Code - EDC § 49133

(a) The school record of the minor giving age, grade, and attendance for the current term signed by the principal or teacher.

(b) Evidence of age, such as the school record of enrollment, or a certificate of birth, or a baptism certificate duly attested, or a passport, or affidavit of the parent, guardian, or custodian of the minor, such as shall convince the officer that the minor is of the age required by law.

(c) The written statement from a prospective employer that work is waiting for the minor and describing the nature of the work.

(d) A certificate signed by a physician appointed by the school board, or by other public medical officer, stating that the minor has been thoroughly examined by him, and, in his opinion, is physically fit to pursue the work specified. No fee shall be charged the minor for the physical certificate.

This section shall be applicable only to minors subject to Section 49130.