Windmill DIY Mechanical House Stem Toys with Instruction Book. The Windmill Kit introduces children to mechanical motion through a cute, buildable windmill house. As kids assemble the rotating blades and decorative structure, they learn how movement is generated and transferred. The included instruction book makes the process easy and engaging, helping develop coordination, logical thinking, and engineering awareness. A charming educational project that blends storytelling, creativity, and STEM learning.