In measuring annual school growth, with approval of the State Board of Education and the Education Oversight Committee, the State shall use a value-added system that calculates student progress or growth. A local school district may, in its discretion, use the value-added system to evaluate classroom teachers using student progress or growth. The estimates of specific teacher effects on the educational progress of students will not be a public record and will be made available only to the specific teacher, principal, and superintendent. Furthermore, the estimates of specific teacher effects also may be made to any teacher preparation programs approved by the State Board of Education. The estimates made available to the teacher preparation programs shall not be a public record and shall be used only in evaluation of the respective teacher preparation programs. Furthermore, educator effectiveness data must be exempt from public disclosure pursuant to § 30-4-30, and may not be subject to the South Carolina Freedom of Information Act. An institution or postsecondary system receiving the estimates shall develop a policy to protect the confidentiality of the data.