Catch up TV
Series 4: 13. Kaleidoscope and Envelope
In today’s episode, Maddie is looking inside things! We look inside a kaleidoscope to learn how it uses three mirrors called a triangular prism to make colourful patterns. Maddie uses a special camera to show exactly how different patterns are made.\n\nNext, she visits a factory where we see how envelopes are made. Lots of paper is used with a very long machine called an envelope machine, which makes the envelopes really, really quickly! Maddie uses a special camera to look at the see-through film that goes over the window on the envelope and lets us see who the letter is for!
Source: CBeebies
Most recent episodes of Do You Know?
Do You Know?
Series 3: 3. Car Engine And Car Transporter
In today's episode Maddie finds out about cars. She heads to a car engine factory and with her special cameras finds out how blocks of aluminium metal are melted and made into a ...
16-09-2025
CBeebies
Do You Know?
Series 3: 2. Plant And Compost
Maddie is finding out about the life cycle of plants! She visits a gigantic tomato growing farm and uses her special time-lapse camera to discover how a plant germinates from a ...
15-09-2025
CBeebies
Do You Know?
Series 3: 1. Skyscraper And Flying Bird
Maddie finds out how really tall buildings are made out of steel and concrete. She visits a skyscraper construction site to explain how the concrete columns that are buried deep ...
12-09-2025
CBeebies
Do You Know?
Series 2: 25. Refrigerator And Mushrooms
In today's episode, Maddie is at home to show us how a refrigerator works. She explains how the pump and the long pipes inside a fridge change a cooling liquid into a gas to hel ...
11-09-2025
CBeebies
Do You Know?
Series 2: 24. Barcode And Fish Cake
In today's episode, Maddie is visiting a supermarket, where she finds out what barcodes are and how they work. At the checkout, we learn how an infrared scanner reads barcodes t ...
10-09-2025
CBeebies
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 ...
09-09-2025
CBeebies
Do You Know?
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 ...
08-09-2025
CBeebies
Do You Know?
Series 2: 21. Fish Tank And Bath
In today's episode, Maddie finds out about things that use water. She visits an aquatic centre to show us how a fish tank works, using a special underwater camera to explain how ...
05-09-2025
CBeebies
Do You Know?
Series 2: 20. Kite And Wind Turbine
In today's episode, Maddie is outdoors finding out about things that use the wind. She finds out how a kite works when it flies high in the sky, shows us how to measure the wind ...
04-09-2025
CBeebies
Do You Know?
Series 2: 19. Television And Carpet
In today's episode, Maddie is relaxing at home, playing games and watching television. She shows us how a television screen works using millions of tiny squares called pixels. U ...
03-09-2025
CBeebies
Most popular episodes of Do You Know?
Do You Know?
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 ...
08-09-2025
CBeebies
Do You Know?
Series 2: 25. Refrigerator And Mushrooms
In today's episode, Maddie is at home to show us how a refrigerator works. She explains how the pump and the long pipes inside a fridge change a cooling liquid into a gas to hel ...
11-09-2025
CBeebies
Do You Know?
Series 3: 1. Skyscraper And Flying Bird
Maddie finds out how really tall buildings are made out of steel and concrete. She visits a skyscraper construction site to explain how the concrete columns that are buried deep ...
12-09-2025
CBeebies
Do You Know?
Series 2: 24. Barcode And Fish Cake
In today's episode, Maddie is visiting a supermarket, where she finds out what barcodes are and how they work. At the checkout, we learn how an infrared scanner reads barcodes t ...
10-09-2025
CBeebies
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 ...
09-09-2025
CBeebies
Do You Know?
Series 2: 21. Fish Tank And Bath
In today's episode, Maddie finds out about things that use water. She visits an aquatic centre to show us how a fish tank works, using a special underwater camera to explain how ...
05-09-2025
CBeebies
Do You Know?
Series 2: 19. Television And Carpet
In today's episode, Maddie is relaxing at home, playing games and watching television. She shows us how a television screen works using millions of tiny squares called pixels. U ...
03-09-2025
CBeebies
Do You Know?
Series 2: 20. Kite And Wind Turbine
In today's episode, Maddie is outdoors finding out about things that use the wind. She finds out how a kite works when it flies high in the sky, shows us how to measure the wind ...
04-09-2025
CBeebies
Do You Know?
Series 2: 18. Lift And Spacesuit
In today's episode, Maddie is finding out about things that go up and down. She shows us how a lift works, when it carries people up and down between floors of a building. With ...
02-09-2025
CBeebies
Do You Know?
Series 3: 2. Plant And Compost
Maddie is finding out about the life cycle of plants! She visits a gigantic tomato growing farm and uses her special time-lapse camera to discover how a plant germinates from a ...
15-09-2025
CBeebies