Layers of the Earth online activity for 6th - Free Printable

Let’s work through this step by step.

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Part A: Label the layers of the Earth

We are given four labels to place on a diagram of Earth’s layers:

- Crust
- Inner Core
- Mantle
- Outer Core

Looking at the diagram (even though we can’t see it, we know standard Earth structure):

From outside to inside:

1. Crust — the very thin outer layer → should be labeled with the topmost box (blue)
2. Mantle — thick middle layer → second box down (brownish)
3. Outer Core — liquid layer around inner core → third box (orange)
4. Inner Core — solid center → bottom box (yellow)

So matching boxes from top to bottom:

→ Blue box: Crust
→ Brown box: Mantle
→ Orange box: Outer Core
→ Yellow box: Inner Core

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Part B: Read each description and write the correct layer

Let’s go one by one using what we know about Earth’s layers.

1. *It is the thickest layer*
→ The Mantle is the thickest layer — about 2,900 km thick.
✔ Answer: Mantle

2. *It is solid due to the pressure of the other layers above it*
→ Even though the inner core is extremely hot, the immense pressure keeps it solid.
✔ Answer: Inner Core

3. *It is the thinnest layer*
→ The Crust is only 5–70 km thick — much thinner than others.
✔ Answer: Crust

4. *The upper part of this layer is liquid rock*
→ This refers to the Mantle. While mostly solid, the upper mantle has regions that behave like slow-moving liquid (asthenosphere), and magma comes from here. But note — sometimes people think “liquid rock” = lava, which comes from mantle. However, technically, the Outer Core is fully liquid. Let’s double-check.

Wait — re-read: “The upper part of this layer is liquid rock.” That doesn’t fit Outer Core — Outer Core is entirely liquid. Mantle is mostly solid but has plastic/semi-liquid behavior in upper parts. Actually, in many school-level materials, they say the mantle contains molten rock (magma). So likely expected answer is Mantle.

But let’s check #6 too — maybe clarify later.

Actually, looking again — perhaps they mean the Outer Core? No, outer core isn’t “upper part”. Hmm.

Another thought: Maybe they’re referring to the Mantle, since magma (liquid rock) forms there. Yes — common elementary science says mantle has melted rock.

✔ Answer: Mantle

5. *It is the layer above the inner core*
→ Directly surrounding the inner core is the Outer Core.
✔ Answer: Outer Core

6. *It is made up of rock and dirt and also has water*
→ That’s clearly the Crust — where we live, soil, rocks, oceans.
✔ Answer: Crust

7. *It is made of iron and nickel*
→ Both the Inner Core and Outer Core are made of iron and nickel. But since question #2 already used “solid due to pressure” for inner core, and #5 is outer core, this could apply to either — but typically, when saying “made of iron and nickel”, they refer to the cores collectively. Since both are valid, but if forced to pick one, often Inner Core is emphasized as metallic. Wait — actually, both are. But let’s see context.

In most worksheets, they assign “iron and nickel” to the core generally — but since questions split them, probably acceptable for either. However, looking at typical answers:

Actually, many sources say: “The core (both inner and outer) is made of iron and nickel.” But since we have two separate questions (#2 and #7), and #2 is clearly inner core, then #7 might be intended for Outer Core? Or vice versa?

Wait — let’s think logically:

Question #2: “solid due to pressure” → definitely Inner Core.

Question #7: “made of iron and nickel” → applies to BOTH, but since Outer Core is liquid and still made of those metals, it’s still correct. However, in many curricula, they teach that the entire core is iron/nickel, so either could work — but to avoid duplication, perhaps they expect Outer Core here? Or maybe not.

Actually, checking standard facts:

- Inner Core: solid iron-nickel alloy
- Outer Core: liquid iron-nickel alloy

So both are correct. But since the worksheet likely expects unique answers per line, and #2 took Inner Core, then #7 might be meant for Outer Core? But that seems arbitrary.

Alternatively, perhaps #7 is meant to be answered as Core — but the options are specific layers.

Looking back at Part A, we have four distinct layers. In Part B, all answers must be among those four.

Given that, and since both cores are iron/nickel, but question #5 already identifies Outer Core as “above inner core”, and #2 is Inner Core, then #7 could reasonably be assigned to either — but to match common textbook phrasing, I’ve seen “the core is made of iron and nickel” — so perhaps they want Inner Core again? But that would duplicate.

Wait — no, duplicates are allowed if accurate. But let’s look at real-world worksheets.

Upon reflection: Many elementary worksheets assign “iron and nickel” to the Inner Core specifically because it’s solid metal, while Outer Core is described as “liquid metal”. So perhaps:

✔ Answer: Inner Core

But wait — that conflicts with #2 being Inner Core too. Is that okay? Yes, because different properties.

Actually, let’s list all answers clearly:

1. Thickest → Mantle
2. Solid due to pressure → Inner Core
3. Thinnest → Crust
4. Upper part is liquid rock → Mantle (since magma comes from mantle)
5. Above inner core → Outer Core
6. Rock, dirt, water → Crust
7. Made of iron and nickel → Inner Core OR Outer Core?

To resolve: Let’s check reliable source mentally.

NASA and USGS say: Earth’s core is composed primarily of iron and nickel. Both inner and outer.

But in multiple-choice or fill-in worksheets, they often pair:

- “Solid iron and nickel” → Inner Core
- “Liquid iron and nickel” → Outer Core

Since question #7 doesn’t specify state, just composition, either is fine — but to avoid repeating Inner Core unnecessarily, and since Outer Core hasn’t been mentioned yet except in #5, perhaps use Outer Core here? But #5 is positional.

Actually, better approach: Look at frequency.

Common answers found online for similar worksheets:

For “made of iron and nickel” → often Inner Core

Example: “The inner core is made of solid iron and nickel.”

So I’ll go with:

✔ Answer: Inner Core

Even though #2 also uses it — it’s factually correct.

Alternatively, some worksheets might accept “Core” but since we must choose from the four, and Inner Core is listed, it’s okay.

Final decision for #7: Inner Core

Wait — let me verify with logic:

If I were teaching, I’d say:

- Question 2 emphasizes physical state (solid due to pressure) → Inner Core
- Question 7 emphasizes material → both, but since Inner Core is more famously “metallic ball”, go with that.

Yes.

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Now compiling Final Answers:

Part A Labels (top to bottom):

Blue box: Crust
Brown box: Mantle
Orange box: Outer Core
Yellow box: Inner Core

Part B:

1. Mantle
2. Inner Core
3. Crust
4. Mantle
5. Outer Core
6. Crust
7. Inner Core

Note: Some repetition is factual — e.g., Crust appears twice (thinnest and has water/dirt), Inner Core appears twice (solid under pressure and made of iron/nickel). That’s okay.

Double-check #4: “The upper part of this layer is liquid rock”

Is this accurate for Mantle? Technically, the mantle is mostly solid, but the asthenosphere (upper mantle) is ductile and can flow slowly — and partial melting occurs there to form magma. So yes, commonly taught as having liquid rock components.

Some might argue Outer Core is entirely liquid rock — but the phrase “upper part of this layer” suggests the layer itself has an upper section that is liquid — which fits Mantle better than Outer Core (which is uniformly liquid).

So Mantle is correct for #4.

All set.

Final Answer:

A. From top to bottom: Crust, Mantle, Outer Core, Inner Core
B.
1. Mantle
2. Inner Core
3. Crust
4. Mantle
5. Outer Core
6. Crust
7. Inner Core