Koguma-kai - Product Name: Seesaw Set Price: 3,400 yen Used, but still usable. After understanding the basic concept of "heavier things go down" by comparing items you have at home, let's compare the weights of boxes. Think carefully about how to compare them to determine the order of weight before you begin. Having a plan will help you develop the ability to think about problems in a systematic way. *This product does not support the study of equilibrium. I am also selling other items for entrance exams. #ElementarySchoolEntranceExam #Koguma-kaiSeesaw