Regarding your question should force be used on children, no, there shall be no forcing the children to do anything. Child should not be forced. This is all nonsense. Who has devised these things? If we want them to become great devotees, then we must educate the children with love, not in a negative way. Of course, if they become naughty we may show the stick but we should never use it. Child is nonsense, so you can trick him to obey you by making some little story and the child will become cheated in the proper behavior. But never apply force, especially to his chanting and other matters of spiritual training. That will spoil him and in the future he will not like to do it if he forced.