
So you want to build the tallest building on Earth? Ambitious but good on yer! This episode will tell you how, starting with how not to. \n\nMost tall buildings are tall and thin because land is expensive. But this isn’t the best design because the lowest floor has to take the weight of all the floors above it. And so eventually, you reach a limit where the structure at the bottom isn’t strong enough. \n\nIf you want to make a building significantly higher, then you need to change the shape and instead take inspiration from wedding cakes. The bottom layers of a wedding cake get wider and wider, which means that they can take more and more weight. In fact, the tallest building ever conceived, the X-Seed 4000, is 4km high and can house a million people - but it’s never been built. \n\nHowever, even if you made a giant cone-shaped building, and assuming you have materials that are strong enough, then eventually you would reach another limit, when the weight of the building is too much for the ground below. That’s why mountains have a maximum size. So, if you want to go higher still, you need to go to the moon, where gravity is lower and so you can go six times higher. But then that wouldn’t be the tallest building on Earth, would it?!
Source: CBBC
Series 2: 10. Your Mind Could Move Things
We imagine a world where it's possible to move things with your mind like films, but find that the laws of physics mean that this superpower wouldn't quite work like you'd expect.
02-10-2026
CBBC
Series 2: 9. We Had Two Suns
There is a way that Earth could have a second sun, so we try it out to see what happens.
01-10-2026
CBBC
Series 2: 8. You Were Invisible
We try out three potential ways to become invisible and discover some surprising side effects.
30-09-2026
CBBC
Series 2: 7. You Could Shout Round The World
Find out how to shout from one side of the world to the other.
29-09-2026
CBBC
Series 2: 6. You Lived On Venus
Venus has acid rain, crushing pressure, and is hotter than an oven, so it might not sound like the ideal place to live. However, up in the clouds it's almost just like home.
28-09-2026
CBBC
Series 2: 5. You Could Stop Global Warming
Imagine if we had a thermostat that could turn the world temperature down - could we fix global warming? But be careful, a few degrees too far could cause an ice age.
25-09-2026
CBBC
Series 2: 4. You Needed Two Of You
From cloning to 3D printing, what if we could actually make copies of ourselves?
24-09-2026
CBBC
Series 2: 3. We Got Rid Of Bugs
Bugs might be annoying, but we would soon regret it if we got rid of them - all our favourite foods would disappear, and there would be dung everywhere!
23-09-2026
CBBC
Series 2: 2. You Walked Through Walls
Wouldn't it be cool to be able to walk through walls? From turning into a gas to quantum trickery, we discover why it wouldn't be quite as useful as you'd like.
22-09-2026
CBBC
Series 2: 1. You Built A Mega Slide
Could you build a slide to the other side of the world? You would need to start in space, use the slippiest slide ever and make sure you have enough supplies before you go down it!
21-09-2026
CBBC
Series 2: 9. We Had Two Suns
There is a way that Earth could have a second sun, so we try it out to see what happens.
01-10-2026
CBBC
Series 2: 5. You Could Stop Global Warming
Imagine if we had a thermostat that could turn the world temperature down - could we fix global warming? But be careful, a few degrees too far could cause an ice age.
25-09-2026
CBBC
Series 2: 6. You Lived On Venus
Venus has acid rain, crushing pressure, and is hotter than an oven, so it might not sound like the ideal place to live. However, up in the clouds it's almost just like home.
28-09-2026
CBBC
Series 2: 8. You Were Invisible
We try out three potential ways to become invisible and discover some surprising side effects.
30-09-2026
CBBC
Series 2: 20. You Threw A Ball Round The World
To throw a ball around the world, you need to start out in space, throw it ten times the speed of a bullet and make sure your ball does not explode when it hits the atmosphere.
27-04-2026
CBBC
Series 1: 11. We Could Actually Stop Climate Change?
The planet is being destroyed - but this episode demonstrates the things you can do to help save it.
22-05-2026
CBBC
Series 2: 16. Money Grew On Trees
If you had a tree that could grow money, would that make you rich? Even if you wait 20 years for your tree to grow, you will probably end up no richer than you started.
21-04-2026
CBBC
Series 2: 3. We Got Rid Of Bugs
Bugs might be annoying, but we would soon regret it if we got rid of them - all our favourite foods would disappear, and there would be dung everywhere!
23-09-2026
CBBC
Series 1: 15. Everything You Touched Turned To Gold?
What if you could turn things to gold? This episode shows that it might not work out that well.
18-06-2026
CBBC
Series 2: 4. You Needed Two Of You
From cloning to 3D printing, what if we could actually make copies of ourselves?
24-09-2026
CBBC