This book is a quick and effective refresher of the mathematics commonly covered in middle school. I currently am tutoring two children in middle school math and so I have been regularly reviewing that specific content. Fundamentally the material being reviewed is basic number theory, exponents and roots. The general tactic is to put forward a short section of explanatory text followed by a set of related short problems and then detailed solutions. The fundamental assumption made by the creators is that you have seen it before, just need to be reminded in a challenging way. If you have a need to relearn the material covered in junior high math classes for any reason, this book is a good choice.