Cal. Educ. Code § 46144

The minimum day in a special day or a Saturday vocational training program and for a pupil enrolled in a work experience education program approved under Article 7 (commencing with Section 51760) of Chapter 5 of Part 28, except for a pupil enrolled in a continuation school or class pursuant to Section 48402, is four periods totaling at least 180 minutes in duration, except that for a pupil in an approved work experience program who attends a school, other than a continuation school or class, in which the regularly scheduled period is greater than 60 minutes in length, the minimum day is one or more periods totaling at least 180 minutes in duration.