The Layers Of The Earth
The layers of the Earth are the distinct shells of material that make up our planet, stacked from the surface down to the centre. There are four main layers: the crust (the thin, solid outer skin we live on), the mantle (the thick middle layer of hot rock that flows very slowly), the outer core (a layer of liquid molten metal), and the inner core (a solid ball of metal at the centre). Together they reach roughly 6,400 km from the surface to the middle of the Earth.
These layers form because of heat and pressure. The deeper you go, the hotter and more squeezed the material becomes — the inner core is hotter than the outer core, yet it stays solid because the enormous pressure stops the metal from melting. The mantle's slow-flowing rock is what drives moving continents, earthquakes and volcanoes at the surface.
Learners come away knowing the order of the four layers from outside to centre, why temperature rises with depth, and the surprising fact that the outer core is liquid while the even-hotter inner core is solid.
▶ Play the lesson — free, no signup
Want to create your own Spark? Sign up free — type any skill and LearnBuddy builds you a playable lesson.
Sign up free to create your own SparkWhat this Spark covers
-
Welcome explorer!🌍🔥 The Layers of the Earth Our planet looks like a smooth blue marble from space. But deep inside, it is built like a giant jawbreaker sweet — layer upon layer, getting hotter and hotter as you go down! Imagine digging a tunnel straight down through Singapore… past the rocks, past glowing hot melted rock, all the way to a metal ball as hot as the Sun's surface. Ready? Tap Next to begin the journey. 👇
-
Earth's 4 main layersEarth has 4 main layers Tap each coloured ring to discover its name. Try to light up all four! CORE 👆 Tap a ring… Each layer is a different colour. Tap from the outside in! 0 of 4 layers found
-
The Crust🪨 The Crust — our home The crust is the thinnest layer, but it is the only one we ever stand on. Soil, rock, the seabed, and every building in Singapore rest right here. How thin is "thin"? If the whole Earth were the size of an apple 🍎, the crust would be as thin as the apple's skin. Cool fact: the deepest hole humans have ever dug still didn't even poke all the way through the crust! Quick check — tap the answer: Which layer do we live on?
-
The Mantle🌋 The Mantle — the giant middle Below the crust is the mantle, the thickest layer of all. It is made of hot rock that is so warm it can slowly flow, like very thick honey or stiff toffee — but it takes thousands of years to move just a little. Watch the mantle creep — tap the button to give it a slow swirl. hot flowing rock 🔁 Make it flow
-
It gets HOT🌡️ Deeper means hotter The closer you get to the centre, the hotter it becomes. Drag the slider to take a lift from the crust all the way down to the inner core! ~20°C 🪨 Crust Nice and cool — about room temperature, where we live. Slide all the way to the centre to feel the heat 🔥
-
Solid or liquid?A tricky twist 🤔 Here's the surprising part most people get wrong: The outer core is so hot it is liquid (melted metal). 💧 The inner core is even hotter — but the huge weight pressing down squeezes it solid. 🧊 Tap-to-reveal: guess each one, then tap to check.
-
Build the Earth🧩 Build the Earth! Put the layers in the right order — from the outside (top) to the centre (bottom). Drag the cards to rearrange them. ✅ Check my order
-
You did it!🌍🏆 You're an Earth Explorer! From the top to the centre, here is your journey: 🪨 Crust — thin outer skin; we live here. 🌋 Mantle — thickest layer; hot, slow-flowing rock. 🟠 Outer Core — liquid melted metal. ⚪ Inner Core — solid metal ball, as hot as the Sun's surface. Remember the big idea: The deeper you go, the hotter it gets — and Earth is built in layers, like a jawbreaker sweet. Well done, explorer! 🎉
Frequently asked questions
- What are the four main layers of the Earth?
- From the outside to the centre they are the crust, the mantle, the outer core and the inner core. The crust is the thinnest and the mantle is the thickest.
- Why is the inner core solid if it is the hottest layer?
- The inner core is under enormous pressure from all the layers pressing down on it. That pressure squeezes the metal so tightly that it stays solid even though it is hotter than the liquid outer core.
- Which layer of the Earth do we live on?
- We live on the crust, the thin outermost layer. All the soil, rock, seabed and buildings — including everything in Singapore — sit on top of the crust.
- Why does it get hotter as you go deeper into the Earth?
- Heat left over from when the Earth formed, plus heat from natural radioactive material inside, makes the temperature rise the closer you get to the centre. The inner core can reach thousands of degrees Celsius.
- What is the mantle made of?
- The mantle is made of hot, dense rock. It is so warm that the rock can slowly flow like very thick toffee, even though it is mostly solid, and this slow movement helps cause earthquakes and volcanoes.
More Sparks like this
Related practice papers
Loved this Spark? Sign up free for AskBuddy AI tutoring, past-year papers, and unlimited Sparks.
Sign up free →