No joint school or department of any kind shall be established, unless the several districts intending to establish the same shall first enter into and record in their respective minutes a written agreement, by and among themselves agreeing that such proposed joint school or department shall be established and maintained by the several districts, in such manner and proportion, and upon such terms as the several districts may then agree upon, and no change shall be made therein without the consent of each school district first obtained, by the affirmative vote of a majority of the school directors thereof.
24 P.S. § 17-1703