In this well-illustrated book the authors, Sinan Kanbir, Ken Clements, and Nerida Ellerton, tackle a persistent, and universal, problem in school mathematics--why do so many middle-school and secondary-school students find it difficult to learn algebra well? What makes the book important is the unique features which comprised the design-research approach that the authors adopted in seeking a solution to the problem.

The first unique feature was that the authors offered a historical overview of the history of school algebra. Despite the fact that algebra has been an important...