Section 26B. If said school committee, upon determination by it of sufficient need, votes that said services should be established by it, it shall submit in writing a plan of said services to the commissioner of elementary and secondary education for his written approval; provided, that said extended school services proposed in said plan shall consist of such care as shall be determined by standards established by said commissioner in consultation with the state department of public health and shall be operated by said school committee under the general supervision of said commissioner; and provided further, that said school committee shall establish as one of the rules of admission of any such child to the benefits of said extended school services that the parents of such child shall pay toward the cost of said services such sum as said school committee shall determine. For the purposes of clause (2) of section five of chapter forty, the establishment and maintenance of said extended school services shall be deemed to be included within the term ”support of public schools”.