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 3: 19. Library And Book
In this episode, Maddie find out about books! First, she visits a library to learn how all the different types of books are stored in different sections. Then she uses her speci ...
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Maddie's Do You Know: At Christmas: 1. Reindeer And Christmas Decorations
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Series 3: 20. X-ray And Sock
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Series 3: 18. Waves And Ice Cream
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Series 3: 17. Lighthouse And Bathbomb
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Series 3: 16. Metal Recycling Centre And Road Sign
Today Maddie is learning about metal, and how it can be recycled and used again. Maddie visits a recycling centre where they recycle metal from old cars. She uses her special ca ...
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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 ...
22-11-2025
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Series 3: 14. Digestion And Meringue
Maddie learns what happens to food in our bodies when we eat it and why it’s important to eat a variety of different foods from different food groups. We find out which fo ...
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Series 3: 13. Beehive And Mug
Maddie visits beehives on the roof of a building in the city. She finds out how honey bees make honey in the hive. Maddie puts on a special beekeeping suit before the beekeeper ...
15-11-2025
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Series 3: 12. Bowling Alley And Ribbon
Maddie heads to a bowling alley to find out how it works. She takes her special cameras and looks behind the lane to see where the pins end up and how they get put back in the r ...
09-11-2025
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Most popular episodes of Do You Know?
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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 ...
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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 ...
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Series 4: 5. Drinking Water And Carrot
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Series 1: 20. Eggs And Bread
Maddie is making breakfast in the kitchen. She visits a farm to see where eggs come from and uses a special thermal imaging camera to show why eggs change colour when they're co ...
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Series 2: 7. Canal Lock And Gate
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Series 3: 2. Plant And Compost
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Series 2: 17. Bubbles And Chocolate
In today's episode, Maddie is having a party! She finds out how bubbles work when we blow into bubble mixture. She shows us how the surface tension of water changes when we add ...
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Do You Know?
Series 2: 16. Posting A Letter And Colouring Pencils
In today's episode, Maddie is sending a letter in the post to the CBeebies house. She finds out how posting a letter works as she follows the letter's journey from the post box ...
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Do You Know?
Series 2: 23. Prosthetic Limb And Detection Dog
In today's episode, Maddie is looking at the way things are made or trained to help us. First, she meets seven-year-old Anu, who uses a prosthetic leg. Maddie visits a workshop ...
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Do You Know?
Series 1: 19. Dishwasher And Table
Maddie is in the kitchen. She uses a special waterproof camera to see how the dishwasher works to clean dirty dishes. An animation shows what happens inside once the door is clo ...
30-07-2025
CBeebies