(a) Every teacher who is employed in grades kindergarten through five for a period of time of more than one-half of the class periods of the regular school day shall be provided a daily lunch period of not less than 30 consecutive minutes, and such employee shall not be assigned any responsibilities during this lunch period. Such lunch period shall be included in the number of hours worked, and no local board of education shall increase the number of hours to be worked by an employee as a result of such employee's being granted a lunch period under the provisions of this Code section. This duty-free lunch period shall not be calculated under any circumstances as a part of any daily planning period or other noninstructional time.

(b) Nothing in this Code section shall be construed to prevent any teacher from exchanging that teacher's lunch period for any compensation or benefit mutually agreed upon by the employee and the local superintendent of schools or such superintendent's agent, except that a teacher and the superintendent or agent may not agree to terms which are different from those available to any other teacher granted rights under this Code section within the individual school or to terms which in any way discriminate among such teachers within the individual school.

(c) The implementation of this Code section may not result in a lengthened school day.

(d) If necessary where due to extreme economic conditions or an unforeseen and unavoidable personnel shortage, a local unit of administration may require a teacher otherwise entitled to a duty-free lunch period to supervise students during such lunch period but for no more than one day in any school week.

(e) Notwithstanding any of the foregoing provisions of this Code section to the contrary, nothing in this Code section shall require the General Assembly to appropriate funds for the implementation of the duty-free lunch program; provided, however, that any such funds appropriated for this purpose shall be used by local school systems for duty-free lunch periods for classroom teachers in grades K through 5.