Ohio Revised Code, Seciton 4109.10 requires a written agreement to wages between a minor and their employer.

The following form is furnished as an example, and may be reproduced by any employer. This form should be prepared in duplicate and signed by both the employer and the minor. One copy to be given to the minor and the other copy to be retained by the employer in the personnel file of the minor. 

For more information, see the Ohio Department of Commerce website.