A Steve Spangler Science Classic! Amaze everyone by blowing up a Windbag with just 1 breath! How many breaths does it take to inflate an 2 m (8 ft) 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 one breath! If you don’t believe it, try this amazing science activity! Windbags are so light and strong that even the smallest scientist can demonstrate the amazing properties of air! How does it work?Tie a knot in the end of the 2 m x 25 cm (8 ft x 10 in) bag and stretch it out on a smooth surface. Blow into the bag using the special science secret and your Windbag inflates with one breath! The Activity Guide is filled with fun science experiments. What does it teach? Use this air-mazing experience to learn about the properties of air molecules and how they move. Demonstrate the scientific principle called the Bernoulli Effect, which explains why you can blow up the amazing Windbag with only one breath! Expand your focus and use this opportunity to discuss how air pressure creates weather systems that move across the continents and how airplanes fly!