California Code, Education Code - EDC § 51403

Elementary school diplomas granted by the governing board of a school district may be on blanks furnished by the Superintendent of Public Instruction or on forms provided by the district, which shall be subject to the approval of the Superintendent of Public Instruction.  All diplomas shall be signed by a majority of the members of the board or its designated representative.  Facsimile signatures or signature stamps may be used for this purpose.