California Code, Education Code - EDC § 81936.5

Bonds may be sold at either public or private sale. The board may fix terms and conditions for the sale or other disposition of any authorized issue of bonds. The county treasurer, when authorized by resolution of the board, may sell bonds at less than their par or face value, but no bond may be sold at a price below the par or face value thereof which would result in a sale price yielding to the purchaser an average of more than 12 percent per annum, payable semiannually, according to standard tables of bond values.