Catch up TV
Series 1: 16. Lock & Key and Glass
Maddie explores the house. She uses a special camera and animation to see how a key works inside a lock and shows how the hidden barrel and pins inside the lock work, to allow the matching key to unlock it. Next, Maddie shows how sand is made into glass. She visits a glass-blowing workshop to see how sand is turned into molten glass and then worked by the glassmaker into a brightly coloured glass vase.
Source: CBeebies
Most recent episodes of Do You Know?
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Series 1: 12. Helicopter Rotor And Tricycle
Maddie is out and about exploring different ways to travel. She visits an airfield and uses a special camera to find out how the rotor works to help make a helicopter fly. An an ...
18-07-2025
CBeebies
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Series 1: 11. Popcorn And Pasta
Maddie explores some favourite foods. She uses a special slow-motion camera to find out why popcorn pops. An animation shows what popcorn is made of and how a water droplet hidd ...
17-07-2025
CBeebies
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Series 1: 10. Water Park And Ice Cream
Maddie goes for a fun day out. She visits an indoor water park and uses a special waterproof camera and animation to show how a water slide works. She then goes underneath the s ...
16-07-2025
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Series 1: 9. Hot Water And Toothpaste
Maddie is preparing for bath time. She uses a special thermal-imaging camera to find out how the hot water system in a house works and then visits a reservoir to see where the w ...
15-07-2025
CBeebies
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Series 1: 8. Blood Pressure Monitor And Cast
Maddie visits a hospital. She uses a special light to see the blood vessels under her skin and finds out how a blood pressure monitor works to check that blood is flowing freely ...
14-07-2025
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Series 1: 7. Boat Propeller And Hot-air Balloon
Maddie is out and about exploring different ways to travel. She uses a special underwater camera to see a boat propeller in action and an animation reveals how the propeller pus ...
11-07-2025
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Series 1: 6. Cat Flap And Woolly Hat
Maddie meets some furry friends. She uses special cameras to find out how a digital cat flap works and how a tiny microchip unlocks the cat flap so the cats can go in and out of ...
10-07-2025
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Series 1: 5. Bike Chain And Tennis Ball
Maddie is outside being active. She uses a special camera to find out how the chain on a bicycle works to turn the wheels and how the front wheel and handlebars are used to stee ...
09-07-2025
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Series 1: 4. Bin Lorry And Newspaper
Maddie does the recycling. She uses a special camera to find out how a bin lorry works to lift a bin and tip the rubbish into the hopper. An animation reveals how a moving wall ...
08-07-2025
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Series 1: 2. Fire Engine Hose And Reflective Strips
Maddie looks at the emergency services. She uses a special camera to find out how the hose on a fire engine works and how the pump inside the fire engine creates pressure and se ...
07-07-2025
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Most popular episodes of Do You Know?
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Series 4: 5. Drinking Water And Carrot
In this episode, Maddie visits a reservoir that collects water from our homes, natural springs and the rain. She heads to a draw-off tower, which takes water from the reservoir ...
11-04-2025
CBeebies
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Series 1: 7. Boat Propeller And Hot-air Balloon
Maddie is out and about exploring different ways to travel. She uses a special underwater camera to see a boat propeller in action and an animation reveals how the propeller pus ...
11-07-2025
CBeebies
Do You Know?
Series 1: 2. Fire Engine Hose And Reflective Strips
Maddie looks at the emergency services. She uses a special camera to find out how the hose on a fire engine works and how the pump inside the fire engine creates pressure and se ...
07-07-2025
CBeebies
Do You Know?
Series 1: 25. Cake And Soft Play
Maddie is getting ready for a party. She uses a special camera and animation to find out how cake ingredients work together to make cake sponges rise in the oven. Next, Maddie v ...
05-06-2025
CBeebies
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Series 1: 21. Magnets And Teddy Bears
Maddie is looking at toys. She uses a special slow-motion camera to find out how the magnets on a train set work. An animation shows how the north and south poles on magnets wor ...
30-05-2025
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Series 2: 22. Hand Dryer And Toilet Roll
In today's episode, Maddie is looking at things we use when we go to the toilet. She visits a factory to see how hand dryers work. She shows us how infrared light is used to swi ...
09-04-2025
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Series 4: 11. Snail And Tractor
Today, Maddie learns about how different things move! She is heading to a snail garden to see how a snail uses mucus and the muscles in its body, called its foot, to move. Maddi ...
21-04-2025
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Series 3: 15. Clouds & Rain And Radiator
In today’s episode, Maddie is finding out about the weather. She discovers why we have clouds and rain and how the water cycle works. We learn there are lots of different ...
24-11-2023
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Series 4: 6. Radio Telescope And Maze
Today, Maddie is finding things! First, she visits an observatory to see how a really big radio telescope uses powerful computers to collect radio waves from space and turn them ...
14-04-2025
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Series 2: 13. Hairclippers And Ballet Shoes
Today, Maddie is dressing up. She visits a barber to find out how clippers work to cut hair. Using a special microscope camera, Maddie shows us how the blades work, and a slow-m ...
24-06-2025
CBeebies