For thousands of years, the Great Wall of China has stretched across China's Northern provinces. It winds like a giant, sleeping dragon from the Pacific coast in the east to the Gobi Desert in the west. But, it's not the only wall in China. Learn about the building techniques used, the empires who constructed them, and what their purposes were over the centuries in this informative book. Put your walking shoes on and get ready to explore all the interesting facts and wonders of the Great Wall of China! This title will allow students to define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost.