Discovery

Use the question "What effect does wind have on different objects?" as your criterion for selecting various materials for this activity. You'll need a fan as a wind source and a variety of common objects. The students will discover that wind can make things move, so be sure to include things that the wind can and cannot move. It's a good idea to have a few fans available so that small groups of students have adequate opportunity to investigate the materials provided. The following list represents suggested materials. Your class may think of many other items from which to explore the effects of the wind.

Suggested Materials

1. Small brown paper bags, a variety of colored pens and pencils and a variety of stickers
2. Ping pong balls, feathers, small rocks, foam packing peanuts, small bits of paper, paper clips, tissue paper, rubber bands, balloons, cotton balls, toothpicks, pencils, sheets of paper, grass, leaves, erasers, bottle caps, empty cans of soda, full cans of soda, dryer lint, paper cups, baby powder and small twigs

Procedure

1. Prior to the discovery part of this activity, distribute one brown paper bag, colored markers or pencils and stickers to small groups. Have students personalize their "wind bags" by decorating the outside of the bag with drawings of "windy" pictures or stickers. While the students are decorating, you may have an open discussion about "windy" things. "What does it mean to call someone a windbag?" "How do you get the wind knocked out of you?" "What impact did the wind play in such movies as The Wizard of Oz?"
2. Collect their personalized wind bags and tell them that they will use them later to discover more about the wind. Fill the wind bags with an assortment of materials for discovery, and then staple or tape them shut.
3. Redistribute the wind bags when you are ready to do the exploration. Assign each group to an electric fan. Ask them to evaluate the effects of the wind on a variety of objects. Before turning on the fans, have the groups examine the materials enclosed in their wind bags and predict the effect the wind will have on each object.
4. Now have the groups turn on their fan and observe what happens. Have them record their observations, any patterns they see, and any questions they think of as they explore. Depending on the materials provided to each group, you can further challenge them by asking questions: "Using wind, how far can you make one object go?" "How much sound can one object make?" "How fast will an object travel?" "How high will an object go?"

Explanation

Wind is air in motion. It has mass and, though extremely light, has substance. A gallon of air is similar to a gallon of water, but the gallon of air is lighter. It has less mass than water because air is less dense. It is more diffused. Like any moving substance, whether it's water plummeting over Niagara Falls or a car speeding down the highway, moving air and water have kinetic energy. This energy of motion gives wind its ability to make objects move. Different objects or combination of objects move differently in the wind.

Examples from everyday life:

• Seeds are moved by the wind. This helps the seed to move away from the parent plant so that it can find enough space, light and water to grow into a new plant.
• Birds "ride the wind" by taking advantage of the thermal updrafts created by air being heated and rising.
• Sailboats and wind surfers use the wind to travel across lakes and rivers. Can the students think of any other examples?

Review

• How well did the students predict the effects of the wind and describe the effects of the wind on various materials?
• What conclusion did they draw while doing the investigation? (Wind makes things move. When we describe a windy day we're usually describing things affected by the wind.)
• What did this exploration tell them about the wind? (Wind is a form of energy.)