Cal. Ed. Code § 40085.5
Applicants seeking to renew a certificate to drive a transit bus as defined in Section 642 of the Vehicle Code shall have successfully completed at least eight hours of original or renewal classroom instruction, or behind-the-wheel or in-service training during each 12 months of certificate validity. In-service training credit may be given by a state-certified driver instructor of the appropriate class, or an instructor certified pursuant to subdivision (d) of Section 40081, to an applicant for attending or participating in appropriate driver training workshops, driver safety meetings, driver safety conferences, and other activities directly related to passenger safety and driver training. During the last 12 months of the validity of the certificate, the eight hours required shall consist of classroom instruction covering, but not limited to, current laws and regulations, defensive driving, accident prevention, emergency procedures, and passenger loading and unloading. Failure to successfully complete the required training during any 12-month period of certificate validity is cause for the Department of Motor Vehicles to cancel the busdriver certificate. All training required by Section 40089 may be accepted in lieu of the requirements of this section.
Ca. Educ. Code § 40085.5