Mass. Gen. Laws ch. 40 § 13E
Any school district which accepts this section, by a majority vote of the school committee and a majority vote of the legislative body or, in the case of a regional school district by a majority vote of the legislative bodies in a majority of the member communities of the district, may establish and appropriate or transfer money to a reserve fund to be utilized in the upcoming fiscal years, to pay, without further appropriation, for unanticipated or unbudgeted costs of special education and recovery high school programs, out-of-district tuition or transportation. The balance in such reserve fund shall not exceed 2 per cent of the annual net school spending of the school district.
Funds shall only be distributed from the reserve funds after a majority vote of the school committee and a majority vote of the board of selectman or city council, or, in the case of a regional school district by a majority vote of the board of selectmen or city council in a majority of the member communities of the district.
The district treasurer may invest the monies in the manner authorized in section 54 of chapter 44 and any interest earned thereon shall be credited to and become part of the fund.
Mass. Gen. Laws ch. 40, § 13E