Section 16C. The regional school district shall be subject to all laws pertaining to school transportation; and when the agreement provides for the furnishing of transportation by the regional school district, the regional school district shall be obliged to provide transportation for all school children in grades kindergarten through twelve and the commonwealth shall reimburse such district to the full extent of the amounts expended for such transportation, subject to appropriation; provided, however, that no reimbursement for transportation between school and home shall be made on account of any pupil who resides less than one and one-half miles from the school of attendance, measured by a commonly traveled route. The commonwealth shall further reimburse such district to the full extent of the amounts expended for the transportation of pupils between school and a child care center licensed or approved by the department of early education and care or a child care facility which is part of a public school system or a private, organized educational system, in accordance with standards approved by the school committee; provided, however, that no reimbursement shall be made if the distance between the school and said facility is less than one and one-half miles, measured by a commonly traveled route, nor shall reimbursement be provided for transportation to a day care facility located outside the boundaries of the regional school district. The state treasurer shall annually, on or before November twentieth, pay to the regional school districts, subject to appropriation, the sums required for such reimbursement and approved by the commissioner of education. Regional school districts may establish a Regional School Transportation Reimbursement Fund. Reimbursements made by the commonwealth pursuant to this section may be deposited into the fund and may carry forward for 1 fiscal year.