According to the World Heal th Organization, around 6 to 8 percent of chi ldren have delay development in fine motor skill. In addition, with the increasing awareness regarding medical care, parents have been paying close attention to their child' s development, and the cases reported have been increasing every year. Unfortunately, products that satisfy children and parents' needs are quite rare. T' Monster is a set of hand training teaching aids that combine light and sound effects. Other than attracting a child' s attention with the colorful and cute appearance to encourage them to play with these. Each monster is designed to focus on different muscle groups of the hands to address different training purposes. For example, when interacting with the Kuba monster, not only are the fine movements, muscle coordination, etc. of the hands worked on, but also the autonomy of the child is strengthened and the foundations for independence are established.