Description Math Board Game Week 1: Number Splitting - Subtraction equations and number splitting - Subtracting from numbers 5 and under - Subtracting by crossing out - Subtracting by comparing Week 2: Ladder Calculations - Measurement calculations - Robot subtraction - Number box calculations - Rule-based calculations Week 3: Paths With Equal Differences - Puzzles - Arrow rules - Tutankhamun game - Matchstick calculations Week 4: Domino Splitting - Making numbers that fit given conditions - Subtraction tables - Matchstick puzzles - Numbers represented by animals - Answer key Bonus Materials (1) The standard study period for one workbook is one month. Week 1, which teaches the basic principles of calculation, consists of 6 pages per day, while Weeks 2 through 4, which build thinking skills based on those basic principles, consist of 4 pages per day. (2) To help children move smoothly through Weeks 2, 3, and 4, a 'Calculation Skills Check' is included at the end of Week 1 so that children can confirm they have mastered the fundamental concepts and review as needed. (3) The difficulty level of the workbook increases gradually — from Week 1 to Week 4 within each book, 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 workbook includes activity stickers, activity sheets, intuitive examples, and various helpful hints. (5) Bonus 1: Math Board Game — Each workbook includes one math board game so that parents and children can enjoy playing together while reinforcing the basic calculation principles from Week 1. Rather than relying solely on repetitive drills, this fun board game helps improve both the accuracy and speed of children's calculations. (6) Bonus 2: Praise Stickers — Recognizing that children can easily lose motivation, a 'Praise Sticker' spot is included in the bottom right corner of the final page of each day's lesson to encourage continued learning. Rather than a single generic phrase, the praise stickers come in three levels — 'Excellent!', 'Great Job!', and 'Keep Trying! You Can Do It!' — to match each child's progress and effort. (7) Bonus 3: Calculation Champion Certificate — A certificate is included at the end of each workbook to motivate children as they move on to the next level. When paired with genuine praise and enthusiastic encouragement, this certificate helps children build lasting confidence in math. (8) The Mathtian website (http://www.mathtian.com) offers a variety of additional learning resources, including: 1) Supplementary calculation problems 2) Thinking-skills activity sheets (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 thinking-based Facto Math - Q&A related to published workbooks - Preparation materials for gifted education programs (past exam questions and practice problems) - Elementary math tips and Q&A