Kentucky Fried Chicken [KFC] / employment

My son is 16 years old. Law states 10pm school nights and 1030 pm on weekends. My son has been staying to 1015pm to 1030. While manager let’s everyone else out at 10pm and makes him stay to do dishes and other chores. The best park she punches him out at 10pm. My son will not work for free and will not be made to stay passed the time the law states. I am going to pursue this further and he will be giving his notice. I am contacting the labor board on this as well. I am sure my child is not the first to be going through this. Not only is he a honor student with a GPA if 3.75 he works three jobs and maintains his academic scores. So he definatley is not a lazy kid or just looking for a way out. Please see too it that this matter is resolved so another child don’t have to deal with this unprofessional work place.
Thank You,
Lisa Audette