Visual Circlemaths Book 1 a Parent Teacher Guide to Speed Subtraction and Long Division
by Robert Michael Taylor
After reading this book you may find your ability to mentally subtract has increased enormously. You will calculate faster. Also you will discover a way to do long division without needing to know any of the "terrible times tables" at all, a way so simple you can successfully teach it to a five year old. The book is written in an easy to read manner for parents, children and teachers.