Whenever a district has been declared duly and finally organized, the members of the board shall qualify by filing with the county clerk their oaths of office, which shall be in the form prescribed by the constitution, and such board members shall also file with the county clerk corporate surety bonds to be furnished at the expense of the district, the form and amount thereof to be fixed and approved by the county commission, and said bonds to be conditioned for the faithful performance of their duties as directors.