The Voyage of a Water Molecule We frequently describe the water cycle as a circle involving evaporation, condensation, precipitation and back to evapo...
The Voyage of a Water Molecule We frequently describe the water cycle as a circle involving evaporation, condensation, precipitation and back to evaporation. While this is not incorrect it certainly doesn’t take into account the whole story. There are many forms of precipitation and much movement of water between precipitation and ultimately the evaporation back into the sky. This activity, inspired by Project WET’S “The Incredible Journey”, is meant to highlight all the various travels that a single water molecule can take. Materials:
9 picture cards (one for each station-see appendix) 9 cubes (one for each station-see appendix) Voyage of a Water Molecule worksheet (see appendix) Pencils, Pens, or Markers
Set Up:
Find an open area in your classroom or elsewhere in your school. Outdoors can work if it isn’t too windy. Place the picture cards and cubes around the area. Have students sit near for a quick introduction.
Procedure: First ask students what they think when they hear the term “water cycle”. Chances are you will get a variety of answers. Have them think a bit more about places around the earth where water can be found. Make a list of their suggestions. Tell them that for this activity you will focus on nine of those places: clouds, plants, animals, rivers, oceans, lakes, ground water, soil and glaciers. 1. Explain to students that they are going to become water molecules to model movement through the water cycle. 2. Separate students evenly among all nine stations. Have them make a line.
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3. Explain how the students will model the movement of the water molecules from one location to another. Water often moves in its liquid form. When the students are moving as liquid water they will travel in pairs, representing the many molecules in a drop of water. If they move to clouds (evaporate) they will move alone as individual water molecules, representing the rapid movement of water in its vapor form. When one student rolls the cube and moves from the cloud station (in the form of precipitation) they will pair up with the next student in line and move to the proper station. 4. Have the students mark their starting location on the worksheet. The roll of the cube will determine the voyage of the water molecules. The first two students in line at each station should roll the cube. If it says stay have them move to the back of the line at the same station. Mark the station in the second block on the worksheet. If it has a new location the students should move as a pair to the new station (unless it is cloud) and mark it on their worksheet. 5. This can continue as long as you would like. There are enough spots on the worksheet for thirty turns, but you may want to stop them earlier or perhaps allow them to continue. A good idea it to set up a buzzer, whistle or sound at the start so the students know when to stop moving around. Wrap-Up and Conclusion: What should the students be learning from this activity? The main idea to get across is that the water cycle involves more than the circle they often see. Water is the basis for life on earth and travels through all parts of the globe. Sometimes water can be trapped in a certain location for hundreds of years, ie: in a glacier. An interesting extension to this activity is to tabulate and graph the number of turns the students spent at each station. You could have them do this individually or as a whole class. Then it would be easier to see where these water molecules tend to collect across the globe. Appendix: Cube cards: page numbers 3-11 Picture cards: page numbers 12-20 Voyage Worksheet: page number 21, 22
