Cal. Educ. Code § 81935

When the bonds authorized to be issued under this chapter are duly executed, they shall be sold by the county treasurer, for cash, in such parcels and numbers as directed by the board, after a resolution requesting the sale has been adopted by the board. Before offering any of the bonds for sale, the treasurer shall detach therefrom all coupons, if any, which have matured or will mature before the day fixed for the sale.