Teachers in the Division shall be eligible for a one (1) year or two (2) year leave of absence without pay. Such leave shall not constitute a break in tenure or loss of accumulated sick leave; but shall not count in calculating experience for increment purposes. Upon return, the said teacher will be assigned by the Board to a teaching position. Eligibility for leave under this Article will exist once every five (5) years during the teacher's employment with the Interlake School Division.