All rules should be worked out in examples or illustrations and
visually impressed upon the child's mind. One visual impression is
equal to about twenty repetitions. Many times children get the idea
that the problem cannot be worked unless the exact "Rule in the book"
is followed. See to it that your children get a broader idea and
that they understand the reason for doing a thing. The training in
mathematics, that is of most value after school days are over, is,
where we understand the reason and have worked out for ourselves the
correct result, independent of any set rule for working the problem.
When helping the child at home give him practical examples from every
day life as well as those in the book.