Effective parents are in charge of their children. Sure, the child has free will. You will do what I say, or you won't be free.
Once the kids are teens, it's too late. By that time, if the parents haven't taught them how to behave, then the kid's free will is strong enough to rebel. That's why children must be taught while they are children.
You must raise the child while the child is a child. At that time, the parent's free will is a lot stronger than the kid's.
If you sit then in the corner for a 5 minute time out what is to stop them from standing up and going outside to play? It will take something other than arm twisting to get a child to perform well in school.