Wind Sock

[20 Minutes]

Because the earth's surface is heated unevenly, the air above it is in constant motion. Cold air is heavier than warm air, so it sinks, forcing lighter, warm air to rise. The upward movement of warm air in the atmosphere produces updrafts. You may have seen birds soaring on updrafts. At the surface, two places can often have differences in temperature and, therefore, differences in air pressure,. These differences cause air to move from the area of higher pressure to the area of lower pressure. This horizontal movement of air is called wind. Create a wind sock to show the direction and strength of the wind.

You'll need:

• large sheet of construction paper • tape • markers • streamers or holiday tinsel • hole punch • yarn or light-weight string

What to do:

1. If possible, print out these directions. Read them through with your child before you begin.
2. With your child, gather everything you’ll need.
3. Let your child draw some weather pictures on a large sheet of paper.
4. Help him roll the paper into a tube and fasten it with tape.
5. At the end of the tube that you want to be the top, let him punch two holes; 1-2 inches from the top on each side. Thread yarn or string through the holes for hanging.
6. Let your child tape or staple streamers or tinsel to the bottom of the tube.
7. Together, find a place to hang the wind sock and watch it's movements.

How to use:

1. Try making other wind socks and experimenting with different diameters (the distance across the circular ends of your tubes). Try different weights of paper too.
2. Try hanging the wind sock in a wide open area. Together, see if you can decide which direction the wind is coming from. Hang the wind sock in a fairly protected area such as the side of your house or from a tree.

Let's Talk: Ideas to Explore Together.

• How does the wind sock let you know that there is any wind at all?
• How do you know when the wind is strong, or there is a gust?
• How do you think wind socks would be helpful to meteorologists, the people who study weather? (Your child may have seen a meteorologist on TV.)