Catch up TV
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 a filter works inside a tank to help keep the water clean and free from fish waste. Next, Maddie visits a factory to find out how bath tubs are made. Starting with a thin sheet of plastic, she shows us how the bath is moulded by air suction. She uses a special camera to explain how a fibreglass gun is used to make the bath strong enough for us to use.
Source: CBeebies
Most recent episodes of Do You Know?
Do You Know?
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
Do You Know?
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
CBeebies
Do You Know?
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: 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
CBeebies
Do You Know?
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
CBeebies
Do You Know?
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
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 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 ...
04-07-2025
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 ...
03-07-2025
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 ...
02-07-2025
CBeebies
Most popular episodes of Do You Know?
Do You Know?
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
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: 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 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
CBeebies
Do You Know?
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
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
Do You Know?
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
Do You Know?
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
CBeebies
Do You Know?
Series 4: 4. Hula Hoop And Tent
Maddie is playing outdoors. She finds out how we move our bodies to keep a hula hoop up in the air and learns how a hula hoop uses something called centripetal force to keep it ...
10-04-2025
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 ...
02-07-2025
CBeebies