Measuring and Graphing Toy Water Animal Growth

Stan Mraz, North Park Elementary School, Columbia Heights School District #13, original idea that adds to FOSS extensions on the Measurement Kit, p.28.
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In this guided inquiry-based lesson, students will participate in a science lab activity by selecting and submerging a growing water animal toy, predicting and measuring its growth of at least three places of metric measurement of distance (total length, height, circumference of head, etc.) over a period of time determined by the teacher. The data (length of body part and time elapsed) will be collected and graphed in the students' science notebooks. The students will share their findings with their classmates using a two-coordinate graph.

Learning Goals

While conducting the measurement inquiry lesson, the students will:
-Identify that the standard unit for measurement is the meter and that millimeters and centimeters are the appropriate unit of measurement used for measuring smaller distances.
-Measure and compare body dimensions of the growing water animal over time.
-Use scientific thinking process to conduct investigations and build explanations: observing, communicating, comparing and organizing.

Context for Use

This lesson is appropriate for grades 3-5 with cooperative groups of 2-3 students.

Students should already know and have had several experiences with how to determine linear measurement of a variety of shapes.

Students should also have an understanding of absorption and how different materials react when submersed in water.

Different submersible animals can be bought on-line (usually in large bulk orders) or through a variety of stores.

Description and Teaching Materials

In this guided inquiry lesson, groups decide on which water toy animal they want to "adopt" and are also asked to choose three or more parts (e.g. length, height, circumference of the head) of the animal that they would like to measure throughout the growing period of the animal (some submersible animals will take up to 72 hours to reach their absolute growth). Students record in their science notebooks the name of their animal and the three areas that they decided to measure. As a class, decide on appropriate times and the number of times that the students will be allowed to measure and record the data (growth) over several days. After all the data has been collected and graphed, the students are to present their data and share their findings with the class. In addition to presenting their graphs, the students' groups should also share their results to several of the teacher-guided questions (provided in the Teacher Guided Questions section). Two-coordinate graph to document time and amount of growth. (Microsoft Word 35kB Aug31 08)

Teaching Notes and Tips

The time that the toy animals are measured should always be the same to allow the students to create an accurate two-coordinate graph.
After the students complete the activity, and/or as an
extension of the lesson, have students find other things that change in a measurable size. Students can even measure their own growth throughout the year using the metric system.

Teacher guided questions to be discussed and written in the student notebooks.
-How is the water animal toy like a living thing? (Possible Answers: It grew. It eventually stopped growing. All living things need water!)
-According to your data that you collected in your graph, which period did the animal have the largest amount of growth?
-Which body part that you measured had the greatest amount of overall growth?
-How does the line move on the graph that demonstrates to us evidence of growth?
-What are some other possible things that could be measured and graphed over a period of time? (Possible Answers: a plant, height, precipitation, etc.)
-What would happen to the water animals if the container of water was too small?
-What else could you investigate and do an experiment on with your water animals? (Possible Answers: The amount of water they absorb over time. The amount of weight they increase by over time.)

Teaching Materials
-Student notebooks or worksheets with graph paper.
-Transparent containers with enough water that will allow the water toy animal to grow up to 600 % its original size (depending upon the manufacturer).
-Different measuring tools for the groups to choose from (e.g. rulers, measuring tapes). String works well to wrap around areas that curve. The students then straighten the string alongside the ruler to get a measurement of the curve.
-T-Charts (could be drawn or glued into the science notebooks) to document growth.
-Two-coordinate graph (could be drawn or glued into the science notebooks) to document growth and to help predict future growth.


Students can be assessed on their science journal responses to the questions (see teacher guided questions), their two-coordinate graphs and their observations and measurements.


3.1.B.3 - Participate in scientific investigation using appropriate tools.
4.1.B.2 - Collect, organize, analyze and present data

References and Resources