We created playground equipment for preschoolers visiting the Kids Park at Shibaura Institute of Technology. The concept was twofold: first, to stimulate the soles of the feet (through jumping, hopping, etc.) to improve motor skills and balance; and second, to spark curiosity about natural laws through spiral-shaped play equipment, encouraging exploration. The manufacturing process involves shaping expanded polystyrene with a cutter and applying a polyurea coating on top. Polyurea is a rubber-like coating that is slip-resistant and reduces the risk of injury. It also enhances the overall durability of the structure, making it suitable for playground equipment. When installed on-site, many children engaged in the intended play activities, such as jumping like stepping stones, sitting on the structures, and exploring in various styles.