Whenever the board of school directors of any district cannot agree on the terms of its purchase with the owner or owners of any real estate that the board has selected for school purposes, such board of school directors, after having decided upon the amount and location thereof, may enter upon, take possession of, and occupy such land as it may have selected for school purposes, whether vacant or occupied, and designate and mark the boundary lines thereof, and thereafter may use the same for school purposes according to the provisions of this act:¹ Provided, That no board of school directors shall take by condemnation any burial ground, or any land belonging to any incorporated institution of learning, incorporated hospital association, or unincorporated church, incorporated or unincorporated religious association, which land is actually used or held for the purpose for which such burial ground, institution of learning, hospital association, church, or religious association was established.