Description [Composition and Features] (1) Each volume is designed for one month of standard study. In Week 1, children learn basic calculation principles with 6 pages per day. In Weeks 2-4, children build on these basics to develop thinking skills with 4 pages per day. (2) To help children move smoothly through Weeks 2, 3, and 4, an "Operations Skill Check" section is included at the end of Week 1, allowing children to confirm they have solidly mastered the basic concepts and providing extra practice if needed. (3) The difficulty level is designed to gradually increase — from Week 1 to Week 4 within each volume, from Day 1 to Day 5 within each week, and from page 1 to page 4 within each day. (4) To support self-directed learning, the books include activity stickers, worksheets, intuitive examples, and a variety of helpful hints. (5) Bonus 1: Math Board Game Each volume includes one math board game so that parents and children can enjoy playing together while reinforcing the basic operation principles learned in Week 1. Rather than relying on repetitive drills, this fun board game helps improve both the accuracy and speed of calculations. (6) Bonus 2: Praise Stickers Recognizing that children can easily lose motivation, a space for a "praise sticker" is included in the bottom right corner of the last page of each day's lesson. Instead of a single generic phrase, the stickers come in three levels — "You're the Best!", "Great Job!", and "Keep Trying, You Can Do It!" — to match each child's level of achievement. (7) Bonus 3: Math Champion Certificate A certificate is included at the end of each volume to motivate children to continue on to the next book. With plenty of praise and enthusiastic applause alongside the certificate, children can build real confidence in math. (8) The Mathtian website (http://www.mathtian.com) offers a variety of additional learning materials, including: 1) Supplementary operation practice problems 2) Critical thinking operation worksheets (9) The Facto Cafe (http://cafe.naver.com/factos) provides a wealth of information and resources related to math education, including: · Free video lectures on creative critical-thinking math (Facto) · Q&A about published books · Preparation materials for gifted education programs (past and predicted exam questions) · Elementary math tips and Q&A