Use dichotomous keys to identify plants like poison ivy (so you can avoid them)! Learn about the diversity of animals and their interactions, from the ocean's bottom to the tallest rainforest trees, from the tiniest microbes and bacteria to the fiercest sharks!

Meet a volcanologist, take a quiz about how Earth changes, or read an interview with a rock from Mars. There's a wealth of support material about Earth's layers, resources, and climate.

Discover the role of energy in retreating ice shelves and in the formation of planets. Read how gravitational force acts on the planets as they journey around the Sun. See how this same force plays out in black holes.