Oregon Revised Statutes Education and Culture § 342.513

(1) Each district school board shall give written notice of the renewal or nonrenewal of the contract for the following school year by March 15 of each year to all teachers and administrators in its employ who are not contract teachers as defined in ORS 342.815. In case the district school board does not renew the contract, the material reason therefor shall, at the request of the teacher or administrator, be included in the records of the school district, and the board shall furnish a statement of the reason for nonrenewal to the teacher or administrator. If any district school board fails to give such notice by March 15, the contract shall be considered renewed for the following school year at a salary not less than that being received at the time of renewal. The teacher or administrator may bring an action of mandamus to compel the district school board to issue such a contract for the following school year.

(2) This section is not effective unless teachers or administrators notify the board in writing on or before April 15 of acceptance or rejection of the position for the following school year.