Introduce a simple version of the water cycle by displaying a water cycle chart and discussing the basic parts of the cycle (condensation, precipitation, evaporation). Relate the cycle to the children's lives. For example, ask questions like "How many of you have played in a puddle? What happens to the puddle after the sun comes out? Did you know that is part of an important science concept called the water cycle?" To illustrate precipitation, freeze a mirror and place it over steaming water. Catch the drops of condensation on a piece of construction paper. Ask children to predict what will happen before conducting the experiment. Discuss what happens during the demonstration. Ask children to draw a picture of the experiment.
Ask children to predict if a variety of objects will sink or float in water. Try items like a toy boat, paper clip, pencil, rocks, eraser, plastic cup, rubber duck or a marble. Allow children to come to their own conclusions about what types of items float and sink. Ask leading questions like, "Did all of the large objects sink? Did all of the plastic items float? Is the big rock heavier than the little rock?" Give children a piece of paper with a blank fish tank printed on it so they can illustrate the results of the experiment.
Discuss where drinking water comes from. Ask children if it is OK to drink water from streams, rivers, puddles or lakes. Explain the importance of drinking water that has been treated to avoid getting sick. Illustrate this important concept by showing students a few different jars full of water from different sources. Include water from a home or school faucet, a nearby lake or river, and a puddle. Filter the water into new containers through a coffee filter with a few cotton balls in it to catch debris. Discuss the results with the children. Ask, "Which water looks the cleanest? Dirtiest? Would you drink this water?" Tell the children where each sample came from and discuss the process water must go through to be potable.
Place a rain gauge outside and monitor it daily. Cut pictures of rain and water from magazines and create a collage. Teach children rain-themed songs like, "Rain, Rain Go Away" or "It's Raining, It's Pouring." Craft "rain makers" with the children by sliding toothpicks through paper towel tubes and filling them with beans or rice. Use the rain makers as instruments to accompany songs. Place paper puddle shapes in a path on the floor and challenge children to jump over the puddles.