Ages 7 to 14 years. Sand and soil are both formed from rock. Types of soil form depending on the climate in different parts of the world. The relationship between humans and animals and the soil is a delicate one. Without soil, plants and crops could not grow and animals and wildlife could not live. Children will learn how soil and sand are formed, the importance of soil, soil erosion and pollution concerns, and the types of sand and soil. Topics include: the importance of animals and other organisms to maintaining healthy soil; the ancient practices of farming from around the world, including the irrigation systems of Afghanistan and Pakistan; how deserts, sand dunes, and quicksand are formed, and what types of sand they are made up of; ancient and modern uses of sand and soil from blown glass to mud brick houses; the methods and equipment that scientists and farmers use to test soil.