Cal. Ed. Code § 16091
The board shall prescribe in the detail that it deems necessary, the purposes for which moneys apportioned by it or which it requires the district to contribute toward, or in reduction of the cost of a project, may be expended, and the prescription shall be binding upon the governing board of the district, save as it may be changed or modified by the board for any cause that it sees fit. In determining funds which can be contributed by the district, the board may require the district to contribute unexpended balances of funds earmarked or encumbered by the district for furniture, equipment, or any other lawful purpose. However, the changes or substitutions in the purposes for which the funds were earmarked or encumbered, with respect to the requirement under any apportionment heretofore or hereafter made, may be authorized by the board, or pursuant to its delegation, by the Director of General Services.
Ca. Educ. Code § 16091