Cal. LAB § 1391.2

(a) Notwithstanding Sections 1391 and 1391.1, any minor under 18 years of age who has been graduated from a high school maintaining a four-year course above the eighth grade of the elementary schools, or who has had an equal amount of education in a private school or by private tuition, or who has been awarded a certificate of proficiency pursuant to Section 48412 of the Education Code, may be employed for the same hours as an adult may be employed in performing the same work.

(b) Notwithstanding the provisions of the orders of the Industrial Welfare Commission, no employer shall pay any minor described in this section in his employ at wage rates less than the rates paid to adult employees in the same establishment for the same quantity and quality of the same classification of work; provided, however, that nothing herein shall prohibit a variation of rates of pay for such minors and adult employees engaged in the same classification of work based upon a difference in seniority, length of service, ability, skill, difference in duties or services performed, whether regularly or occasionally, difference in the shift or time of day worked, hours of work, or other reasonable differentiation, when exercised in good faith.