Layers of the Earth Comprehension Worksheet for 10-Year-Olds

Instructions

Read the passage below about the amazing layers hidden deep inside our planet. Once you have finished reading, answer the questions that follow to test your knowledge!

Our Planet's Secret Layers

Have you ever wondered what's inside the Earth? If you could cut our planet in half like an apple, you wouldn't find a core with seeds! Instead, you would see four main layers, each with its own special properties. Let's take a journey to the center of the Earth!

1. The Crust
This is the layer we live on! It's the Earth's thinnest, outermost layer, like the thin skin of an apple. It's made of solid rock and is broken into huge pieces called tectonic plates. The crust under the oceans is called oceanic crust, and the crust that makes up the continents is called continental crust.

2. The Mantle
Just below the crust is the mantle. This is the thickest layer of the Earth, making up about 84% of our planet's volume! The mantle is mostly solid rock, but it's so hot that parts of it can flow very slowly, like thick, gooey honey. This slow movement is what causes the tectonic plates on the crust above to shift, leading to earthquakes and volcanic eruptions.

3. The Outer Core
Deeper still is the outer core. This layer is a real hot spot! It's made of liquid iron and nickel, and its temperature is over 4,400 degrees Celsius. This super-hot liquid metal is constantly swirling and flowing. This movement is incredibly important because it creates Earth's massive magnetic field, which protects us from harmful solar winds.

4. The Inner Core
Right at the very center of the Earth is the inner core. It's a solid ball also made of iron and nickel. You might wonder, "If it's the hottest layer, why is it solid?" That's a great question! It's because the pressure from all the other layers pushing down on it is so immense that it squeezes the atoms together, forcing them to be a solid instead of a liquid.

Part 1: Multiple Choice

Circle the best answer for each question.

1. Which layer of the Earth is the thinnest?
• a) Mantle
• b) Crust
• c) Outer Core
2. The movement in which layer causes earthquakes?
• a) Crust
• b) Inner Core
• c) Mantle
3. Which layer is made of LIQUID iron and nickel?
• a) Outer Core
• b) Inner Core
• c) Mantle
4. What important force is created by the movement of the outer core?
• a) Gravity
• b) The magnetic field
• c) Ocean tides

Part 2: Fill in the Blanks

Use the words from the word bank to complete the sentences.

Word Bank: solid, pressure, thickest, plates, liquid

1. The crust is broken into large pieces called tectonic _______________.
2. The mantle is the Earth's _______________ layer.
3. The inner core is a _______________ ball of metal due to extreme _______________.
4. The outer core is made of _______________ metal that swirls and flows.

Part 3: Label the Earth

Imagine a diagram showing a cut-out wedge of the Earth. Label the four main layers in order from the outside to the center.

A. (The very thin, outermost layer) ______________________

B. (The thick layer beneath the first one) ______________________

C. (The liquid layer after the thick one) ______________________

D. (The solid ball at the very center) ______________________

Part 4: Short Answer

Write your answer in a complete sentence.

1. What are the two main metals found in both the inner and outer cores?
2. In your own words, explain why the inner core is solid even though it is the hottest layer.

Answer Key

Part 1: Multiple Choice

1. b) Crust
2. c) Mantle
3. a) Outer Core
4. b) The magnetic field

Part 2: Fill in the Blanks

1. plates
2. thickest
3. solid, pressure (in that order)
4. liquid

Part 3: Label the Earth

A. Crust

B. Mantle

C. Outer Core

D. Inner Core

Part 4: Short Answer

1. The two main metals found in both the inner and outer cores are iron and nickel.
2. (Answers will vary) A good answer should mention that the immense pressure from the layers above it squeezes it so tightly that it cannot become a liquid.