Grade 3 · Science · Lesson 9

Layers of the Earth

If you could slice the Earth in half like an apple, you would see four distinct layers inside. Each layer has a different thickness, temperature, and composition. Scientists have discovered these layers by studying earthquake waves that pass through the Earth.

What this lesson teaches

1Identify the four main layers of the Earth: crust, mantle, outer core, and inner core
2Describe a key feature of each Earth layer
3Order the four layers from the outermost to the innermost

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