Description Sangwigwon Yeonsan 960 approaches number and calculation learning—the starting point of mathematics and an essential tool across all math domains—with a new philosophy and methodology. Through task-based number and calculation problems combined with diverse situations, processes, and approaches, this workbook not only completes calculation skills but also builds higher-level mathematical thinking. Sangwigwon Yeonsan 960 will be a great strength for children who get bored or tired of simple, repetitive calculation drills; children who need creative, higher-level calculation practice beyond the basics; children working on advanced application of school curriculum; children who need to think through math rather than solve problems mechanically; children who want to build a solid foundation rather than rush into excessive advanced learning; children preparing step by step from an early age for gifted education programs, olympiads, or specialized middle/high schools; and any child who loves math and wants to excel at it. Table of Contents (121-160) Issue 1: Numbers up to 50 Issue 2: Numbers up to 19 (1) Issue 3: Numbers up to 19 (2) Issue 4: Numbers up to 50, Numbers and Problem Solving Answer Key Included