Grade 4 · Science · Lesson 9

Earth's Layers and Tectonic Plates

Earth is made up of four distinct layers, each with different properties. Scientists have learned about these layers by studying earthquake waves that travel through the planet. Understanding Earth's structure also helps us explain earthquakes, volcanoes, and the formation of mountains.

What this lesson teaches

1Name and describe the four layers of the Earth
2Explain what tectonic plates are and how they move
3Describe the effects of tectonic plate movement

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