In addition to all other power and authority which may now be vested in any board of trustees of any school district by the constitution or statutes, or both, of the State of Mississippi, any such board of trustees is hereby vested with the authority to close any one or more or all schools in any school district when, in its discretion, it determines such closure to be to the best interest of a majority of the educable children of the territory served, or to the best interest of a majority of the children enrolled in any such school or schools. Said board of trustees is also vested with the authority, in its discretion, to close any one or more or all schools in any school district when such board, in its discretion, determines such closure will promote or preserve the public peace, order or tranquility of the district.