Mathematical ReasoningTM helps students devise strategies to solve a wide variety of math problems. This book emphasizes problem-solving and computation to build the math reasoning skills necessary for success in higher-level math and math assessments. This book is written to the standards of the National Council of Teachers of Mathematics. The Level D book is a complete curriculum for the third grade level. These highly effective activities take students far beyond drill-and-practice by using step-by-step, discussion-based problem-solving to develop a conceptual bridge between computation and the reasoning required for upper-level math. Activities and units spiral slowly, allowing students to become comfortable with concepts but also challenging them to continue building their math skills. Answers are included in the back of the book.