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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!
Source: CBBC
Most recent episodes of Hey You What If?
Hey You What If?
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!
25-04-2024
CBBC
Hey You What If?
Series 2: 15. You Shrunk The Earth
We find out what would happen if you shrank the earth. You could jump higher and move faster, but you would end up with altitude sickness even at sea level.
22-03-2024
CBBC
Hey You What If?
Series 2: 14. You Built A Giant Sandcastle
Is it possible to build a sand castle the size of a real castle? We imagine how it could be done, using a pneumatic drill and a huge, solid gold steamroller!
21-03-2024
CBBC
Hey You What If?
Series 2: 13. You Were The Last Person On Earth
What would the planet be like if all other humans disappeared, leaving you as the last person on earth?
20-03-2024
CBBC
Hey You What If?
Series 2: 12. You Walked On Ceilings
We try using a gravity-bending black hole and spinning the earth faster to see if we can make it possible to walk on the ceiling..
19-03-2024
CBBC
Hey You What If?
Series 2: 11. Animals Were Supersized
We look at whether some animals can get gigantic and find out that if you are being chased by a giant snail or a humungous butterfly, then fear not, you must be dreaming.
18-03-2024
CBBC
Hey You What If?
Series 2: 26. You Could Walk Up Walls
We take inspiration from the natural world as we imagine a new kind of superhero that can walk up walls.
15-03-2024
CBBC
Hey You What If?
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.
15-03-2024
CBBC
Hey You What If?
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.
14-03-2024
CBBC
Hey You What If?
Series 2: 8. You Were Invisible
We try out three potential ways to become invisible and discover some surprising side effects.
13-03-2024
CBBC
Most popular episodes of Hey You What If?
Hey You What If?
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.
05-03-2024
CBBC
Hey You What If?
Series 2: 7. You Could Shout Round The World
Find out how to shout from one side of the world to the other.
12-03-2024
CBBC
Hey You What If?
Series 2: 14. You Built A Giant Sandcastle
Is it possible to build a sand castle the size of a real castle? We imagine how it could be done, using a pneumatic drill and a huge, solid gold steamroller!
21-03-2024
CBBC
Hey You What If?
Series 1: 26. You Could Fly Like A Bird?
Anyone can fly like a bird – you just have to travel across the solar system to do it!
14-06-2022
CBBC
Hey You What If?
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!
25-04-2024
CBBC
Hey You What If?
Series 2: 11. Animals Were Supersized
We look at whether some animals can get gigantic and find out that if you are being chased by a giant snail or a humungous butterfly, then fear not, you must be dreaming.
18-03-2024
CBBC
Hey You What If?
Series 2: 15. You Shrunk The Earth
We find out what would happen if you shrank the earth. You could jump higher and move faster, but you would end up with altitude sickness even at sea level.
22-03-2024
CBBC
Hey You What If?
Series 1: 9. The Moon Was Made Of Cheese?
Things don’t quite go to plan when the moon turns into cheese.
21-12-2023
CBBC
Hey You What If?
Series 1: 6. You Could Levitate?
Good news - it’s possible to levitate! Bad news – there are some serious side effects.
18-12-2023
CBBC
Hey You What If?
Series 2: 19. You Only Ate Burgers
If everyone in the world ate nothing but cheeseburgers, we would run out of land, and even if we went meat-free, we would have to invent some crazy burgers to get the nutrients ...
28-09-2023
CBBC