Topic
Rocks & ground
Mountains, soil, caves, and what is underfoot — 39 tiny stories from every shelf.
Leftover bricks
What Are Asteroids?
Asteroids are rocky leftovers from when the planets were being built.
Let’s go →A dirty snowball
What Is a Comet?
Comets are icy leftovers that steam into a bright tail near the Sun.
Let’s go →A rusty planet
Why Is Mars Red?
Mars looks red because its dust is literally rusted iron.
Let’s go →Not a star at all
What Is a Shooting Star?
Shooting stars are specks of dust burning up as they slam into our air.
Let’s go →A true space story
Where the Moon Came From
A giant smash long ago threw up the rock that became our Moon.
Let’s go →A definition, not a demotion
Why Is Pluto Not a Planet Any More?
Pluto lost its planet status because astronomers found many similar objects sharing its region of space.
Let’s go →Billions of orbiting snowballs
What Are Saturn's Rings Made Of?
Saturn's rings are billions of separate ice chunks orbiting individually, not a solid hoop.
Let’s go →Our planet is a magnet
Why Does a Compass Point North?
Earth's liquid iron core makes a magnetic field that swings compass needles north.
Let’s go →Fire welds the grains together
Why Does Baking Mud Make Stone?
A brick is mud baked so hot that its grains fuse at the edges and become, in effect, a new stone.
Let’s go →A cliff of tiny shells
What Is Chalk Made Of?
Chalk is soft white rock made from the shells of countless tiny sea creatures that settled on an ancient sea floor.
Let’s go →Flat plates with water between them
Why Can You Shape Clay but Not Sand?
Clay can be shaped because its grains are flat plates that slide on water and stay wherever you leave them.
Let’s go →Sunlight from a very long time ago
What Is Crude Oil?
Crude oil is ancient buried sea life, cooked under rock into a mixture that gets split into fuels and plastics.
Let’s go →The metal that will not change
Why Is Gold So Special?
Gold is prized because it never corrodes, is easy to shape, and is genuinely rare — and it was made in exploding stars.
Let’s go →Water dissolving stone
How Do Caves Form?
Caves form when faintly acidic water slowly dissolves limestone away.
Let’s go →Because it was one
Why Does the Map Look Like a Jigsaw?
South America and Africa fit together because they really were joined, and the sea floor between them is still growing.
Let’s go →Rock finally slipping
Why Does the Ground Shake?
Earthquakes happen when stuck slabs of rock suddenly slip past each other.
Let’s go →Patience with sandpaper
How Do Rivers Carve Canyons?
Rivers cut canyons by dragging sand and stones that grind the rock away.
Let’s go →When the ground stops drinking
Why Do Rivers Flood?
Floods happen when rain arrives faster than the soil can soak it up.
Let’s go →Rock replacing bone
How Does a Fossil Form?
Fossils form when minerals slowly replace buried bone, copying its shape in stone.
Let’s go →A kettle with a narrow neck
Why Does the Ground Shoot Boiling Water?
A geyser erupts because pressure holds superheated water back until a small boil triggers a chain reaction.
Let’s go →Ice that flows
How Do Glaciers Move?
Glaciers are ice piled so deep that it deforms and flows slowly downhill.
Let’s go →Soaked rock, not caverns
Where Is Water Underground?
Groundwater sits in the tiny spaces between grains of rock, not in hidden lakes.
Let’s go →Four different ways
How Does a New Island Appear?
Islands appear in four main ways: volcanic building, coral growth, being cut off, or falling sea level.
Let’s go →Sorted by weight
What Is Inside the Earth?
Earth has layers because heavy metal sank to the centre while it was still molten.
Let’s go →Atoms in formation
What Is a Mineral?
A mineral is a natural solid with a fixed recipe and a repeating atomic pattern.
Let’s go →Crust crumpling
How Do Mountains Grow?
Mountains form where colliding plates crumple the crust upward.
Let’s go →Salt arrives and never leaves
Why Is the Sea Salty?
The sea is salty because rivers deliver salt and only fresh water evaporates out.
Let’s go →The air arrives empty
Why Is One Side of a Mountain Dry?
Air dumps its rain climbing a mountain, so the far side gets dry wind and no water.
Let’s go →Erosion on the outside
Why Do Rivers Bend?
Rivers bend because water cuts the outer bank and deposits on the inner one.
Let’s go →Nothing is permanent
Can a Rock Turn Into a Different Rock?
Rocks continually change type, as heat, pressure and weathering recycle them into one another.
Let’s go →Mountains, eventually
Where Does a Beach Come From?
Sand is what remains after rock is broken down and everything softer has washed away.
Let’s go →Rock, remains and life
What Is Dirt Actually Made Of?
Soil is ground-up rock mixed with decayed remains, air, water and more living things than you would believe.
Let’s go →Pressure finding a way out
Why Do Volcanoes Erupt?
Volcanoes erupt when buoyant molten rock and expanding gas force their way to the surface.
Let’s go →Being eaten by the invisible
Why Do Dead Things Rot?
Rotting is microbes eating dead matter and returning its nutrients to the soil.
Let’s go →Anchor and straw
What Do Roots Do?
Roots anchor a plant, absorb water and minerals, and trade with soil fungi.
Let’s go →Both, in a way
Is Coral a Rock or an Animal?
Coral is a colony of tiny animals living inside a stone skeleton they build.
Let’s go →Reading bones
How Do We Know About Dinosaurs?
We know dinosaurs from fossils, read by comparison with living animals.
Let’s go →Free soil engineering
Why Are Earthworms Useful?
Earthworms improve soil by eating dead matter, mixing layers and making tunnels.
Let’s go →Far, hard and facing you
Why Do Canyons Echo So Well?
Canyons echo because their walls are far away, hard and steeply angled back at you.
Let’s go →