In this Resources video, Science Facilitator Sam demonstrates 3 different air cannons and talks about the science of moving air.
We often think of air as being something light and weightless. In reality, air is a gas that takes up space and has mass (weight). Since there is a lot of "empty" space between air molecules, air can be compressed to fit in a smaller volume. Sometimes it is difficult to think about air and what it does because it is invisible. The air cannon is a way to 'see' air as it moves objects within its 'blast zone'.
Check out the video below and make your own Air Cannon at home or in the classroom. For more great, free activities, check out Air on Science World Resources.