The county board of education may appoint for every school in the county, from a list of six discreet, competent and reliable persons of mature years nominated by the patrons of the said schools, which list shall be kept on file by the board, three persons residing near the schoolhouse and having the respect and confidence of the community to serve for a term of four years as trustees of the school, to care for the property, to look after the general interest of the school and to make to the county board of education, through the county superintendent of education, from time to time, report of the progress and needs of the school and of the will of the people in regard to the school. The board of education, should it decide to appoint school trustees, shall fill all vacancies occurring in the office of trustee for the unexpired term from the list of nominees on file until the names on such list are exhausted. The term "patrons" as used herein shall be construed to mean the parents and guardians of children in attendance at the school.