What do we have in our classroom that has water in it at alltimes? If the room has an aquarium, our project can be done with it. If not, we can fill a jar with water, and keep it on the countertop. In either case, there should be some kind of marker at the top of the water when we begin the experiment. Tape is a good marker, and it can be removed when we have finished.

Having filled and marked a container, or having marked the surface of the water in the aquarium, the next step is to mark the calendar for today's date.

Each day, we will check the level of the water, measure down from the marker, and make a note of the amount of water that has disappeared.

As an added experiment, we will do some small water-color paintings first thing in the morning. Make a note of the time the paintings are finished. Just before lunch time,
feel the paintings and determine whether they are dry or wet. Check them again just before the end of the day.

At your house, does your mom sometimes hang wet clothes on a clothesline or a hanger, and wait until the clothes get dry?

In each instance, there is water, and then it is gone. The water level in aquarium or jar gets lower and lower each day. The paintings are still moist by noon; by the end of the day they are dry. When mom hangs out clothes to dry, she brings them in toward the end of the day, because they are dry.

Where did the water go? Is it magic? We know that gardens and house plants need to be watered because the plants will die without water. But, when we put water on the plants, we know that it doesn't stay there forever; otherwise, we wouldn't have to do it again. The water is there, and then, after awhile, it is gone. What happens to it?

The water is actually absorbed by the air around it. The moisture of the water rises into the air. It is almost like magic, isn't it? The process is called evaporation (pronounced "ee-vapp-o-RAY-shun"). The water goes up into the sky, combines with moisture that is already there and makes a cloud, then comes back down in the form of rain.