Think of it like a ladder. You might not be at the top right now, but each new thing you learn takes you a step closer and means that your parents can relax the rules a little.
Human eyes are very complex and are good at doing many jobs at once, while spiders have different sorts of eyes that do different jobs.
It's true that here on Earth, if you want to burn something you need oxygen. But the Sun is different. It is not burning with the same kind of flame you would have on Earth if you burned a candle.
Being double jointed doesn't mean you have an extra joint – an expert in biomechanics explains what makes some people doubly bendy.
Writing has only been a part of the human story for the last 5,000 years. In comparison, humans began to communicate using speech some 50,000 years ago.
An expert explains all the wonderful ways the atmosphere protects life on Earth.
The short answer is that leeches need blood to grow and reproduce. But it's in their interests to do it carefully, without causing too much pain, and in spots that are hard to find.
Dinosaurs ruled the Earth for about 180 million years. But around 66 million years ago, a huge rock from outer space (called an asteroid) smashed into the Earth. Then things got worse for dinosaurs.
As strange as it sounds, rocks are made from stardust.
Ladybirds do not have tails because they have no backbones.
A scientist explains how global warming is affecting the entire world – from the mountains, to the sea.
We know very little about the deep sea and how its inhabitants, including anglerfish, will respond to change. In fact, more people have walked on the Moon than have been to the bottom of the ocean.
I have been interested in the science of fire and fireworks for a long time, and can tell you there is a lot happening in the very short time it takes to light a match.
Gravity exists because the universe is full of 'stuff' – here's how it came to be.
Some animals, such as ghost shrimps can even cope with water that is saltier than normal seawater. It's all down to evolution.
Waves occur in all sorts of places, and it's possible that waves you might see breaking at the beach are at the end of a very long journey.
All the buildings and the cars and the restaurants, and the phones and even everything that's inside of you... it all started with an exploding star, billions of years ago.
Your teeth started to grow even before you were born.
A sigh is the brain's way of stopping the tiny sacks in your lung from collapsing.
Even fridge magnets have magnetic fields approximately 200 times stronger than Earth's.