All full-time assigned classroom teachers shall be provided duty-free instructional planning time during regular student contact hours. The duty-free instructional planning time shall be provided to the maximum extent that (i) the safety and proper supervision of children may allow during regular student contact hours and (ii) insofar as funds are provided for this purpose by the General Assembly. If the safety and supervision of children does not allow duty-free instructional planning time during regular student contact hours for a given teacher, the funds provided by the General Assembly for the duty-free instructional planning time for that teacher shall revert to the general fund. Principals shall not unfairly burden a given teacher by making that teacher give up his or her duty-free instructional planning time on an ongoing, regular basis without the consent of the teacher. (1983, c. 761, s. 88; 1999-163, s. 1; 2006-153, s. 3.)