Pinwheel Wind Collector

Materials
a pin
a square piece of construction paper (about 5.5" x 5.5")
a sharpened pencil with an eraser
scissors

Procedure

Lay the square of paper flat on a table and draw a line diagonally from each corner to the opposite corner. Mark the center of the square where the two lines cross and punch a small hole through it with the pencil tip. Next, cut along each line stopping about an inch from the hole in the center of the square. Take the pin and punch a hole in the top left corner of each of the four flaps. (No two holes should be next to each other.) Pick up a flap at a punched corner and carefully curve it over toward the center hole, securing it with the pin. Repeat this for the other flaps. When all four flaps are held by the pin, carefully lift the paper without letting the flaps unfurl. Lay the pencil flat on a table and carefully push the point of the pin into the side of the eraser.

Now your pinwheel is complete and ready to go. Pick up the pinwheel near the pencil point and let it catch the wind. Your students should discover that the pinwheel only spins when the wind hits its center.

You now have a simple wind collector. The pinwheel is an example of a horizontal-axis active wind collector. It must be pointed into the wind in order to spin.

Wind Direction Indicator

Materials

one straight plastic soda straw
one piece of construction paper
a pencil with an eraser tip
one straight pin
stapler
scissors

Procedure

Cut one end off the piece of construction paper so that it is square. Fold one corner of the square over until it meets the opposite corner to form a large triangle. Crease the fold and open the paper. Cut along the fold to make two triangles. Fold one triangle in half once again and crease it along the fold. Now place an open edge of this folded triangle over the soda straw with the point toward the center of the straw and the other open edge at the end of the straw. Staple the tail to the straw. Next push the pin through the soda straw about one inch ahead of the front of the tail. Push the pin into the top of the eraser on the pencil. Your wind direction indicator is now ready to go.

Hold the wind direction indicator in the wind. It automatically turns around until the tail of the straw points away from the wind and the tip points into the wind. This instrument is useful in determining where the wind is coming from at any time and in noting variations during the day or from season to season. Hold your wind direction indicator in the wind and notice how often the wind direction changes.