This is part of a series of Instructables intended for teachers about educating students in the classroom around making and tinkering. For more about the details of this project, check out our blog.
CD balloon hovercrafts are a tried and true instructional tool in the classroom for teaching the concepts of friction, air flow, momentum and a host of other physics concepts. There are a lot of other Instructables out there with different methods, like this great one from The Children's Museum of Houston. Use whatever method or materials suit your needs best.
These devices float rather well on any smooth surface, and depending on what size balloon you use and how much air you allow to escape, can work for several minutes at a time. They are quick to make for almost any age. We've added a design challenge component to the facilitation of this activity to both make the device work better and challenge the participants to add their own ideas to the activity. Building a Better Hovercraft is a great way to explain it. Traditional ones get some drag when the balloon deflates enough to tip over - how can we creatively solve this issue to make the hovercrafts travel further and faster? Read on to find out!
We do ours with film canisters and CDs, both items that used to be readily available and either free or cheap. Alas, as the progress of technology marches on, both are becoming less prevalent in the world. You just can't pick up AOL CDs out of the street for this activity anymore! Fortunately, you can still find all of the necessary materials for this activity online and locally.