California Code, Vehicle Code - VEH § 11103

A driving school owner and an independent instructor licensed under Section 11105.5 shall maintain bodily injury and property damage liability insurance on motor vehicles while being used in driving instruction, insuring the liability of the driving school, the driving instructor, and any person taking instruction in at least the following amounts: one hundred fifty thousand dollars ($150,000) for bodily injury to or death of one person in any one accident and, subject to the limit for one person, three hundred thousand dollars ($300,000) for bodily injury to or death of two or more persons in any one accident, and the amount of fifty thousand dollars ($50,000) for damage to property of others in any one accident.

The owner or instructor shall file evidence of that insurance coverage in the form of a certificate from the insurance carrier with the department, and the certificate shall stipulate that the insurance shall not be canceled except upon 30 days' prior written notice to the department.