Catch up TV
Series 1: 7. Clouds Were Made Out of Cotton Wool?
Clouds might look like cotton wool, but if they really were, things would get very messy.
Source: CBBC
Most recent episodes of Hey You What If?
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Series 1: 1. You Fell Into A Black Hole?
Experience the most extraordinary ride in the universe – falling into a black hole.
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Series 1: 16. You Could Actually Reach For The Stars?
Want to reach for the stars? It would be the journey of a lifetime - literally.
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Series 1: 15. Everything You Touched Turned To Gold?
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Series 1: 14. You Could Live On The Moon?
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Series 1: 13. You Could Shrink Yourself?
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Series 1: 12. You Can't Wait For Christmas?
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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.
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Hey You What If?
Series 1: 10. The Earth Was Flat?
Find out why a flat earth would feel very unflat indeed!
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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.
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Hey You What If?
Series 1: 8. The Earth Stopped Spinning?
Find out why stopping the earth from spinning isn’t such a good idea.
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Most popular episodes of Hey You What If?
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Series 1: 21. You Woke Up As A Lizard Superhero?
Why waking up with lizard powers would make you useless on earth but a superhero in space!
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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?
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Flying like a superhero may sound like enormous fun, but there are some serious downsides that Hollywood does not tell you about - weather, extreme cold and even fizzy blood.
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Series 1: 1. You Fell Into A Black Hole?
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Experience the ultimate in long-distance travel - a holiday on Mars!
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Series 1: 18. The Earth Was Shaped Like A Doughnut?
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Series 1: 19. You Could Run At The Speed Of Sound?
A fun run goes wrong when one ambitious runner tries running at the speed of sound.
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Hey You What If?
Series 2: 2. You Walked Through Walls
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