Find an interrelated set of tools--maps, animations, diagrams, photographs, and text--to help you understand tectonic plates and how they move.

This site is a very simple overview of plate tectonics. It includes a map of all the major plates and a diagram of the layers of the earth.

The paths that water can take through Earth's systems are many and complex. Examine the following diagram from NASA depicting the water cycle. Studying the water cycle is important because changes in the water cycle affect all parts of...

This one-page explanation of the rock cycle contains a very helpful diagram and useful explanatory notes. Site explains how rocks are made and broken down.

Learn about the movement of water from Earth's surface to the atmosphere with this site. Site describes the water cycle in words and with a diagram. Also explored on the page is the distribution of Earth's global water supply.