Why do some children struggle with mathematics, while others seem to be naturally gifted? In this book, Caleb Gattegno examines the obstacles that keep students from succeeding in math, and provides a clear solution. Using Algebricks colored rods, parents and teachers can make arithmetic visible, tangible, and rewarding for their learners. Through exploring and playing with the materials, children absorb essential mathematical knowledge, while parents and teachers discover the astounding learning capacity and inventiveness of their children.