Description: This workbook is published to reflect the newly revised 2022 curriculum, effective from 2024. 1. Ten problems solved with the mind matter more than a hundred solved by hand. Operations that only teach calculation methods can build "calculation skills," but they don't necessarily lead to true "math ability." Just as calculations have their own principles and methods, each calculation has its own characteristics and relationships to other calculations. Children also need to be able to apply calculations and develop number sense through them. To enable multi-dimensional training rather than a flat, one-sided approach to calculation, this book is designed with mathematically grounded problems that allow children to think about a single operation from various angles. 2. Math filled with meaning—not just the four operations—builds a strong foundation for elementary, middle, and high school math. Because math is a continuous subject spanning elementary, middle, and high school, the concepts formed in elementary school directly affect learning in later years. Concepts learned in elementary school may seem simple, but they connect to important ideas in middle and high school, making it essential to learn operations in a way that highlights their mathematical meaning. This book also helps children experience, from an elementary level, the mathematical rules they will encounter later, laying a solid foundation for their overall math learning. 3. Math concepts stick only when children think, solve, and truly feel them. Operations that focus solely on repetitive calculation from start to finish can bore children and cause them to miss the mathematical meaning behind the calculations. This book builds a multi-dimensional learning structure that helps children understand the mathematical principles behind each calculation method, connecting practice to real conceptual understanding. The answer key also includes special notes explaining why each concept matters and how it connects to future middle and high school learning. Contents: 1. Addition of proper fractions with the same denominator 2. Addition of mixed numbers with the same denominator 3. Subtraction of proper fractions with the same denominator 4. Subtraction of mixed numbers with the same denominator 5. Addition of decimals with the same number of digits 6. Addition of decimals with different numbers of digits 7. Subtraction of decimals with the same number of digits 8. Subtraction of decimals with different numbers of digits