Parachutes fall slowly because air is trapped beneath drag. Drag is the force that works against the direction of anything that flies through the air. The amount of drag depends on the shape. A fat, lumpy shape, like the parachute in the first project, has lots of drag and falls slowly.
Hot air balloons rise into the air, because the hot air inside them is lighter than the air outside. Real balloons use gas burners, but the project here uses a hair dryer to make the balloon rise.
Felt-tipped pen, a large plate, thin fabric, scissors, needle, thread, tape, plastic thread reel.
Pencil, card, ruler, scissors, sheets of tissue paper, glue stick, hair dryer.
Looking for something? Ask Google.