Explore the theory of place tectonics and learn how volcanoes develop, including 1,500 active sites around the world today. See how volcanic eruptions created the Hawaiian Islands and destroyed the island of Montserrat. Monitor Mexico's Paracutin volcano. Witness the devastation of Mt. St. Helens. Take a terrifying, but fascinating, look at these violent forces that shape our planet.

The digestive tract is a hugely complex arrangement of organs working together in harmony to give your body all the benefits it needs from the food we eat and to protect us from harmful bugs and bacteria. By looking at a typical American family we are able to see how lifestyle, fast foods and work dictate what we eat, how we eat and therefore how well our digestive system works. Eddie the Enzyme pops up with step by step advice, on the do's and don'ts of good digestion. With him and the help of an expert nutritionist we explain precisely what food makes for good digestion.