Why do hot air balloons float? This resource from the NOVA Web site offers a series of interactive activities that illustrates the physics of hot air balloons.

Have you ever wondered how a ship made of steel can float? In this project you'll investigate how much weight boat hulls of various shapes and sizes can support without sinking.

Students will explore matter that sinks or floats when submerged in water and that matter is categorized as either a sinker or a floater. Students will work actively in small, cooperative learning groups as well as gather in a whole...