Except as otherwise provided by an employee's collective bargaining agreement or individual contract, employment between an employee and Niles Community Schools is on an at-will basis. This means that either Niles Community Schools or the employee is able to terminate the working relationship at any time and with or without notice. No individual supervisor, manager or officer can make a contrary agreement, except the Superintendent, and even then, such an agreement must be set forth in a written employment contract with the employee signed by the Superintendent.