When in any city or town a class of twenty (20) or more persons has been organized in accordance with the provisions of § 16-29-11, the school committee shall provide a teacher for this class, and pay the expenses of instruction from the appropriation of the city or town for the support of the public schools. The school committee of two (2) or more adjoining cities or towns may unite for the purpose of establishing and maintaining classes jointly at convenient places as provided in § 16-29-11, and may determine by agreement what part of the cost of maintenance shall be paid by each city or town.
R.I. Gen. Laws § 16-29-12