To have the control and supervision of all public schoolhouses in their district, and to grant the temporary use of them, when not occupied by schools, for religious meetings and Sunday schools, for evening schools and literary societies, and for such other meetings as the board deems proper; to grant the use of assembly halls and class rooms when not otherwise needed, including light, heat and attendants, for public lectures, concerts, and other educational and social interests, under such provisions and control as they may see fit to impose; to grant the use of school grounds under such provisions and control as they may see fit to impose and to conduct, or provide for the conducting of recreational, social and civic activities in the school buildings or on the school grounds or both.