Tsunamis are giant, powerful waves most often caused by earthquakes beneath the ocean floor. Their incredible power can destroy entire communities, then drag the debris out to sea. This video shows what causes tsunamis and the importance of evacuating any area under a tsunami alert.

Bill Nye explains plate tectonics and the origination of its theory. The areas in which the tectonics spread apart is where volcanoes form. Conversely, the areas in which the tectonics come together is where mountains form.

Scrat places a nut on the ground, causing the Earth to split in half. He travels down the layers of the Earth and chases the nut on the Earth's core. This clip comically shows how the different continents and many of Earth's iconic structures formed.

Plate tectonics have shuffled the earth's landmasses around, and continue to do so.

Sabrina explains how the earth changes using seasons and landforms as examples. She illustrates how landforms form and change over time by mentioning plate tectonics, erosion, and weathering. She uses famous examples of gradual change (The Grand Canyon and The Old Man of The Mountain) as well as examples of quick change (Mount St. Helens) to stress that the earth changes in ways that are both noticeable and not so obvious.