Section 14. For any district in which fewer than twenty percent of the students scored below the state average on the assessment tests required by chapter sixty-nine, the city or town, or all cities and towns comprising a regional school district, may exempt the district from the provisions of this chapter by accepting this section in the manner prescribed by section four of chapter four. Any district so exempted shall continue to receive fiscal year nineteen hundred and ninety-three base aid, but shall not receive any additional state aid and shall not be required to meet the local obligation requirements of this chapter.
If, in any future year, a district so exempted fails to meet the assessment standards described above, or for any other reason is not exempt from this chapter, it shall, in that and future years, be subject to the same obligations and entitled to the same aid under this chapter in each year as districts that were never so exempted.