This is a set of three books by Dr. Hiroyuki Yokoyama, who researches developmental disabilities in children and the collaboration between education, health, and welfare. ① Manga de Wakaru Mahou no Homめkata PT: Shikarazu ni Kodomo wo Kaeru Saikyou Method (Understanding the Magic of Praise PT: The Strongest Method to Change Children Without Scolding) - Author: Hiroyuki Yokoyama - Price: 1500 yen + tax ② Manga de Wakaru Yononaka no Rule (Understanding the Rules of the World) - Author: Hiroyuki Yokoyama - Price: 1429 yen + tax ③ Manga de Wakaru Ouchi no Rule: Shougakkou Nyuugaku made ni Mi ni Tsuketai 45 no Shuukan (Understanding the Rules of the Home: 45 Habits to Acquire Before Entering Elementary School) - Author: Hiroyuki Yokoyama - Price: 1200 yen + tax Books ① and ② are in good condition. Book ③ is missing the cover and has some scribbles on a few pages (but they are still readable). Please consider this a used item. Thank you for looking.