California Code, Education Code - EDC § 17307

No contract for the construction or alteration of any school building, made or executed by the governing board of any school district or other public board, body, or officer otherwise vested with authority to make or execute a contract, is valid, and no public money shall be paid for any work done under a contract or for any labor or materials furnished in constructing or altering any building, unless the plans, specifications, and estimates comply in every particular with the provisions of this article and the requirements prescribed by the Department of General Services and unless the approval thereof in writing has first been had and obtained from the Department of General Services.