(a) No child under sixteen (16) years of age, who is employed in any of the several vocations mentioned in this act, or in the transmission of merchandise or messages, or any hotel, restaurant or mercantile establishment shall be employed before 7 a.m., or after 10 p.m., except on any evening that does not precede a school day, nor more than eight (8) hours in any one calendar day, nor more than forty (40) hours in any one week.

(b) The provisions of this section shall not apply to any student engaged in school food service preparation nor shall such provisions apply to the employment of a student-learner who is enrolled in a course of study and training in a cooperative vocational training program under a recognized state or local educational authority, or in a course of study in a substantially similar program conducted by a private school: Provided, That such a student-learner is employed under a written agreement which shall provide: (1) That the work of the student-learner shall be incidental to his training, and shall be under the supervision of a teacher-coordinator employed by the school; and (2) that a schedule of organized and progressive work processes to be performed on the job shall have been prepared. Such a written agreement shall carry the name of the student-learner, and shall be signed by the employer and the school coordinator or principal.