Cal. Education Code § 39800.5

(a) Any school district and any owner or operator of a private school that provides transportation for pupils that owns, leases, or otherwise has possession or control of a 15-passenger van, may not, on or after January 1, 2005, authorize the operation of that van for the purpose of transporting passengers unless the person driving or otherwise operating that van has both of the following: (1) A valid class B driver’s license, as provided in Division 6 (commencing with Section 12500) of the Vehicle Code, issued by the Department of Motor Vehicles. (2) An endorsement for operating a passenger transportation vehicle, as provided in Article 6 (commencing with Section 15275) of Chapter 7 of Division 6 of the Vehicle Code, issued by the Department of Motor Vehicles. (b) (1) Except as provided in paragraph (2), for purposes of this section, a “15-passenger van” means any van manufactured to accommodate 15 passengers, including the driver, regardless of whether that van has been altered to accommodate fewer than 15 passengers. (2) For purposes of this section, a “15-passenger van” does not mean a 15-passenger van with dual rear wheels that has a gross weight rating equal to, or greater than, 11,500 pounds.