Explore the building blocks of our planet with fun jokes, cartoons and hands-on activities. Find out more about different types of soil and how soil is formed. Explore different soil horizons (layers) and discover what they are made of. Learn how living things help to break down soil and how soil helps plants to grow. This book is part of the Geology Rocks series. This collection of books examines the Earth's make up, from the different types of rock it is made from to discovering the structure of the planet itself and how tectonic plates relate to earthquakes and volcanoes. Perfect for readers 7 and up.