There's something interesting that I've heard about recently. I've a friend named Kevin O'Connor and I just realized that he has developed a very special way for dealing with maths.
Yes its not exactly material for us but more so for us to teach our children. With his unique technique, your child will be able to perform lighting fast calculations simply and easily.
What's better. The multiplication tables can be mastered in an amazing 2 hours. Talk about fast :
http://www.vedic-maths-ebook.com/vedic