Ohio Rev. Code § 3319.131
A public school teacher who has completed five years of service may, with the permission of the board of education and the superintendent of schools, be entitled to take a leave of absence with part pay, for one or two semesters subject to the following restrictions: The teacher shall present to the superintendent for approval, a plan for professional growth prior to such a grant of permission, and at the conclusion of the leave provide evidence that the plan was followed. The teacher may be required to return to the district at the end of the leave for a period of at least one year, unless the teacher has completed twenty-five years of teaching in this state.
The board of education may not grant such a leave unless there is available a satisfactory substitute, nor grant such leaves to more than five per cent of the professional staff at any one time, nor allow a part salary in excess of the difference between the substitute's pay and the teacher's expected salary, nor grant a leave longer than one school year, nor grant a leave to any teacher more often than once for each five years of service, nor grant a leave a second time to the same individual when other members of the staff have filed a request for such a leave.
R.C. § 3319.131