Bernoulli Windbags are a Steve Spangler Science classic. You can amaze everyone by blowing up a Windbag with just one breath.
How many breaths do you think it takes to inflate an 8-foot (2-meter) Windbag? 70 breaths, maybe? Why even try?
With a simple science secret, you can amaze your students and friends by blowing up your Windbag in just one breath. Windbags are so light and strong that even the smallest scientist can demonstrate the amazing properties of air.
How Does It Work?
Tie one end of the bag in a knot and stretch it out on a smooth surface. Blow into the bag with just one breath and your Windbag will inflate. There is so much more to this bag than this one property, so we’ve included an Activity Guide filled with more fun experiments.
What Does It Teach?
Use this air-mazing experience to demonstrate the properties of air molecules and how they move. Teach students about the Bernoulli Effect, a scientific principle that explains why you can blow up the amazing Windbag with only one breath.
Expand your lesson and use this opportunity to discuss how air pressure creates weather systems that move across the continents and how airplanes fly.
Windbags Are Not Balloons
You can blow Windbags up, but they do not share the same elasticity of a regular balloon. That means that Windbags are easier to inflate than regular balloons, opening the door for a ton of creative activities.
Build Geometric Shapes
Hook two rubber bands together by laying the windbags on top of one another. Pull the rubber bands through each other in opposite directions. Use the rubber bands to arrange the tubes in various shapes. Make giant cubes, triangles, pyramids or even giant balloon animals.
Save Your Breath With Bernoulli’s Principle
The One Breath Bernoulli Bag experiment from Steve Spangler Science is a great way to show students how they can use science to do things easily and efficiently.
At first glance, these large, colorful windbags will seem impossible to blow up without an air pump, but when children embark on this exciting experiment, they will quickly see that science allows them to easily inflate the Windbag with minimal effort.
They will experience Bernoulli’s principle firsthand, gaining a better understanding of airflow and how it can be used by humans. This simple experiment can inspire a lifelong love of science and curiosity about the world and how it works.
Each Windbag is 8 feet long by 10 inches wide (2 meters by 25 centimeters). We offer Windbags in different pack sizes:
•Pack of 4 (colors will vary)
•Pack of 32 (colors will vary)
Safety Information
Toll Free: 800-223-9080
Monday – Friday
8:30 am – 5:00 pm (MST)
Steve Spangler Science
Denver Office
7901 Southpark Plaza, Suite 106
Littleton, CO 80120
[email protected]
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Gasti –
This year as part of our grade level effort to build community we ordered enough wind bags so that 3 students had a bag (there are 120 students in our grade level) – the challenge to work together to find a way to inflate the bag in as few breaths as possible.Many hundreds of breaths later and a lot of condensation inside the bag (yuck) we had inflated, tied off bags. Then I used one breath by demonstrating the Bernoulli Effect. After a lot of untying they were able to demonstrate the same.The last step was to work together to build a structure within each class. The 4 different colored bags allowed each of our four sections of 4th graders to build structures using tied-off bags and rubber bands. The final design challenge was to conjoin each of the four structures into a multicolored mega-grade-level structure.It is a great first week community building event and it also offers some insight into how different students handle the pressures of time, working in a crunch with others and noise! We used the school gym and it got loud fast with 120 9-10 year olds.This will be an annual event for our grade!
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Bailey Dickie –
My group of preschool aged kids had a blast playing with the Windbags! They were amazed that I was able to blow up the entire bag with one breath. The Windbag itself was very durable and was able to withstand the rough play, tugging and throwing of 3 and 4 year olds! The Windbag truly stood up to claims of being able to be blown up with one breath, and there are many activities that can be done with them. Definitely recommend to any daycare, preschool or group of young kids to play and learn with!
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April Oaks –
I’ve bought LOTS of things on this website… my favorite is these windbags. It’s such an AWESOME tool to teach kids how airplanes fly. In the video the windbags are shown at 50 seconds and 1:01.
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Question
Daniel –
When can we order the windbags? My son seen them on Ryan’s Toy World and we’d like to have them at his Birthday party
I’d like to order 25 pack please asap
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Staff lisabrooks –
Unfortunately, we do not have an ETA at this time. I would recommend checking back in the next two weeks as we hope to have more information by July 1st. Sorry for the inconvenience.
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Question
Bethany Chatham –
What kind of plastic are these made from? Can they be recycled along with plastic shopping bags? If not, is there a way to recycle them?
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joshlittrell –
The Windbags are made of an HDPE plastic. They are not biodegradable so it is important to recycle them, along with all other plastic bags. Please reach out to us with any additional questions.
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Question
Shannon Marengo –
Hello! Are these bags reusable? I worry about germs from student to student if we reuse them.
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ablock –
To stop the spread of germs, we recommend one bag per child.
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Outreach in Ithaca –
This is one of those activities that never fail to get kids excited. Air being transparent, they’re not used to think of it as a mass of fluid that moves and can be moved, so especially with younger kids you have to build up the explanation, but even if they don’t fully understand the physics, it’s so much fun they’ll recall the experiment when they’re in a more advanced science class.
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