The president shall be the executive officer of the board of school directors, and as such he, together with the secretary, when directed by the board, shall execute any and all deeds, contracts, warrants to tax collectors, reports, and other papers pertaining to the business of the board, requiring the signature of the president. In school districts other than in school districts of the first class he shall, after the board has acted on and approved any bill or account for the payment of money authorized by this act, sign an order on the treasurer for the payment of the same. He shall in no case, except as this section otherwise provides, sign any order for any sum unless the same has first been acted upon and approved by the board, and the amount thereof and the name of the payee properly inserted. Any orders which shall be for the payment of amounts owing under any contracts which shall previously have been approved by the board, and by the prompt payment of which the district will receive a discount or other advantage, may be signed without the approval of the board first having been secured. All such orders shall be presented to the board at its next meeting. The president shall perform such other duties as the board may direct and as pertain to his office.