Except as provided in section 3319.36 of the Revised Code, no person shall receive any compensation for the performance of duties as teacher in any school supported wholly or in part by the state or by federal funds who has not obtained a license of qualification for the position as provided for under section 3319.22 of the Revised Code. Any teacher so qualified may, at the discretion of the employing board of education, receive compensation for days on which the teacher is excused by such board for the purpose of attending professional meetings, and the board may provide and pay the salary of a substitute teacher for such days.