Any local or regional school district may take, by eminent domain, land which has been fixed upon as a site, or addition to a site, of a public school building, and which is necessary for such purpose or for outbuildings or convenient accommodations for its schools, upon paying to the owner just compensation, provided such taking is with the approval of the legislative body of the town, and in the case of regional school districts, subject to the provisions of section 10-49a, and in each case in accordance with the provisions of sections 8-129 to 8-133, inclusive. The board, committee or public officer empowered to acquire school sites in such school district shall perform all duties and have all rights prescribed for the redevelopment agency in said sections with respect to such taking. No school district or municipality shall take for school purposes the land of any ecclesiastical society, upon any part of which a church building has already been erected, without the consent of such ecclesiastical society, or any land devoted to or used for cemetery or burial purposes.