Minors who attend regular school may not work in the entertainment industry for the same number of hours as minors tutored by studio teachers. Minors tutored by studio teachers need only be instructed for three hours a day [EC 48224; 8 CCR 11760] while minors in regular school are generally required to attend school for a much longer time. Clearly, minors who attend regular school cannot assume the same workhour burden as tutored minors. Consequently, the Division of Labor Standards Enforcement adopted an enforcement policy for minors who attend regular school. This policy computes the length of the workday for minors who attend regular school by subtracting six hours from the maximum number of hours that tutored minors are permitted on set when school is in session. For example, tutored minors nine to 16 years of age are permitted to be on set for up to nine hours, therefore minors who attended regular school on a workday would be permitted to be on set for up to three hours. Such workdays for minors attending regular school do not require a one-hour rest and recreation period, but they may be extended one-half hour by a meal period. Finally, the Division of Labor Standards Enforcement’s policy always assumes that the minor who attends regular school always attends for at least six hours. Thus, in an effort to safeguard the minor’s educational interests, an artificially shortened regular schoolday is never allowed to result in an employer benefit of extended work hours.

http://www.dir.ca.gov/dlse/ChildLaborPamphlet2000.html#22