Record Keepers. First-Grade. Developing good record-keeping habits is essential for organizing,

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1 Photographs courtesy of the authors First-Grade Record Keepers By Theodora Pinou, Hope A. Flanigan, and Marjorie S. Drucker Young students observe the development of salamander larvae to learn about life cycles and scientists. Copyright 2009, National Science Teachers Association (NSTA). Reprinted with permission from Science and Children, Vol. 46, No. 5, January Developing good record-keeping habits is essential for organizing, processing, and communicating experimental results objectively. We came up with an interactive method of teaching first graders to record, organize, and interpret data as they studied the life cycle of the spotted salamander (Ambystoma maculatum). In our curricular sequence, students recorded the water temperature, date, and number of salamander eggs that hatched. Additionally, students illustrated the salamander s developmental stages over time in a personal journal and learned how to organize data on bar graphs. The experiences enabled us to successfully meet the unit s objectives, which were to (1) describe the uses for a thermometer, (2) organize data in a bar graph reflecting the number of eggs hatched by temperature, and (3) discuss the relationship between temperature and rate of salamander metamorphosis. Our students met these learning goals and more. By the end of the salamander study, in addition January

2 to learning about the salamander s life cycle, students had begun to develop skills to communicate, critique, and analyze their work and the work of their peers. We describe our experiences here to inspire you to try similar units with your young scientists (see sidebar, In Your Classroom, p.33). The Salamanders Are Here Our study began through an external partnership at our school. Coauthor Theodora Pinou an assistant professor and science education coordinator in the Department of Biological and Environmental Sciences at Western Connecticut State University in Danbury, Connecticut works with several local elementary schools and teachers (ours included) on programs to enrich their science curriculums. She procured approximately 45 salamander eggs that she had collected from a local vernal pool (a seasonally filled wetland) for the study and monitored the eggs in the school s science lab, the Discovery Room. The water level of the tanks needs to be checked twice a week, and vernal pool water, which contains protozoa and larval nutrients, needs to be added when it drops to a depth of 3 or 4 cm. The salamander project lasted for about seven weeks. Students completed work in their classroom and also visited the Discovery Room (once a week for the first two weeks and twice a week for the following five weeks). Salamander Background The unit began with a weeklong introduction to salamanders and science skills in the classroom. First the class read The Salamander Room (Mazer 1991) and discussed the book s main idea: what a salamander would need to live in a child s bedroom. Afterward, that same day, they read Let s Measure With Tools (Casteel 2002), and students matched pictures of simple measuring tools to relevant objects, such as a ruler to a pencil, a balancing scale to various fruit, and a thermometer to a picture of a snowy day. On the second day, students learned about salamander metamorphosis from the nonfiction book A Salamander s Life (Himmelman 1998) and used a graphic organizer to record facts. They focused on learning the developmental stages of salamanders: (1) circular egg; (2) bean-shaped egg; (3) eggs with visible larvae; (4) hatched feathery-gilled larvae with long, flat tails; and (5) gilled larvae with tails and limbs. Students were already aware of life cycle changes that many animal species undergo from previous science studies in kindergarten and first grade. This background provided students with a basis for predicting the changes that salamanders may undergo. The teacher and students discussed that unlike a juvenile human (i.e., child) who looks like a miniature adult, a juvenile salamander looks more like a fish that Figure 1. Experimental setup. Photographs courtesy of the authors Observing salamander eggs allowed students to learn about record keeping and life cycles. 32 Science and Children

3 First-Grade Record Keepers Figure 2. Example of student journal illustration. In Your Classroom Schools that are interested in participating in similar activities can contact the Herpetologists Education Committee of the Society for the Study of Amphibians and Reptiles (SSAR) at Ask for a partnering herpetologist that can provide eggs of regional species of amphibians that can be released back into their native habitat once hatched preventing the disruption of the natural biodiversity. Alternatively, the same temperature-dependent metamorphosis investigation can be conducted with fish eggs that can be commercially purchased from biological suppliers such as Ward s Natural Sciences. After 14 days, the eggs in the warmest temperatures have developed into feathery-gilled larvae with long flat tails. Eggs in the coldest temperatures varied from circular eggs to some larger bean-shaped eggs. Eggs at room temperature had both larvae with feathered gills and eggs. The gilled larvae in room temperature didn t have the long flat tails. then changes into a salamander as it grows. Then, students colored the Salamander Life Cycle worksheet from Enchanted Learning to reinforce what they had learned about the developmental stages for salamanders (see Internet Resource). Additionally, the teacher and students discussed that salamander eggs are laid in temporary pools of water in the forest and that environmental factors, such as drought and frost, can therefore have quite an effect on their life cycles. The teacher highlighted temperature change as something to watch. Students were familiar with the temperature variable from a previous unit on weather. During that unit, students had learned about monitoring air moisture and temperature, and light. Therefore, students were prepared to speculate about what would happen to the development of salamander eggs if the temperature were to change over a period of time. The teacher explained that they could place the eggs in different conditions, monitor the temperature with thermometers, and record observations on the external appearances of the eggs and larvae in journals. On day three, the teacher reviewed the skill of measuring temperature. The students had previously been taught the process of recording temperature using an indoor outdoor thermometer on the window of the classroom and through the use of a large-scale cardboard thermometer that uses a red plastic ribbon looped through it to mark a specified temperature. The teacher poured 50 ml of room-temperature water into each of three clear-plastic pint containers. Ice cubes were added to one container, heated water to the second container, and the third container was left as is. Students then used nonmercury thermometers to measure the temperature in each container and recorded the results by placing a red horizontal line at the appropriate temperature on a worksheet. On day four, the classroom teacher introduced the class to bar graphs. Students practiced making bar graphs through counting and sorting manipulatives, which are recorded as pictures or colored squares that represent the objects. For example, the teacher counted plastic green salamanders and gave green squares to each child to represent the salamanders. Students lined up an equivalent number of green squares as salamanders in parallel rows on their desktops. They then represented the salamanders on paper by either drawing salamanders or using salamander stickers. This lineup of green salamanders on paper creates a pictograph. From here, the teacher explained that numbers are another way to represent a lineup of salamanders. Thus, students are introduced to the concept of creating a number scale that can record individual salamanders a bar graph of the information. Later, students applied this skill as they created a bar graph of the number of salamander eggs that hatched in each temperature environment. Discovery Room Learning After these introductory experiences, students visited the Discovery Room to observe the salamander eggs and the January

4 Photographs courtesy of the authors Students were excited to come see the larvae in the lab. experimental setup. The tanks with the eggs were set up with a thermometer upright in the water in each one and appropriately labeled (Figure 1). Tank A (room temperature) was left in the classroom (19 21 C); Tank B (cold) was placed in the refrigerator (4 6 C); and Tank C (warm) was placed in the greenhouse (20 24 C). (If a greenhouse isn t available, a heat lamp can be used to warm the tank water to the desired temperature.) An easel with a data collection sheet was set up next to each tank. First, students used nonmercury thermometers to measure the temperature in the tanks. Then, they were asked to predict in which environment the eggs would hatch first. Students predicted that the eggs in the greenhouse would hatch first because warm, sunny conditions make things grow quickly. Students related changes in temperature to seasonality and rate of growth in plants, an earlier theme covered in their weather unit. Turning students attention to the data-collecting chart, the teacher filled in the first entry for each condition with the date and wrote no (denoting that the eggs had not yet hatched). Finally, students received a journal, recorded the date, and drew what they observed under the words room, hot, and cold. Observing and Recording For the next few weeks, students returned to the Discovery Room twice a week for half-hour visits to record their observations of the three tanks and to observe egg development. Students worked in groups of five and cycled through the tanks to make the process more efficient. In about 7 10 days, the eggs progressed to subsequent developmental stages, such as eggs with visible larvae or hatched feathery-gilled larvae with long flat tails. Students observed these changes and recorded them in their journals with words and illustrations (Figure 2). Children were amazed by the white feathery gills they saw, and they eagerly compared the developmental stages they observed to the salamander life posters that adorned the classroom walls. Within days, the eggs began hatching in the greenhouse. The room-temperature eggs closely followed the greenhouse eggs. Students were fascinated by the transformation, yelling out, I see the gills or I see the legs. Students understood that the gills were going to disappear as the animal metamorphosed from a water breather to an air breather. As students visited the tanks and recorded temperature, the teacher asked if any group had observed hatching and, if so, how many eggs or larvae. Students recorded this data on a class data collection chart. In a whole-group setting, the teacher worked with the children to draw a pictograph of the information recorded in the class data-recording sheet that was transformed into a bar graph and displayed in the classroom (Figure 3). The class began to reflect on their original question regarding development and temperature. This discussion was initiated with guided questions such as, Why do you think the eggs are hatching faster in the greenhouse? The teacher was able to bring together earlier concepts students had learned that focused on animal responses to seasonal temperature changes. Some animals slow down their metabolic rates and hibernate; other animals speed up their rates and grow very quickly. Students have read books in class that link global warming to increases in temperature and what effects this rise in temperature may have on animal life cycles (Brett 2004; Mayer 2008; Willow 1991). The recording procedure continued until the refrigerated eggs hatched, a few days later. At this point, the larvae were returned to their native habitat by the school partner. For future classes, we are considering ways to include student field trips for the release of the larvae so that students can be a part of the process. Salamander larvae with feathery gills and long tails. 34 Science and Children

5 First-Grade Record Keepers Figure 3. Example of a bar graph. The teacher formatted the graph so students could focus on displaying their data. Connecting to the Standards This article relates to the following National Science Education Standards (NRC 1996): Content Standards Grade K-4 Standard A: Science as Inquiry Abilities necessary to do scientific inquiry Understanding about scientific inquiry Standard C: Life Science Characteristics of organisms Life cycles of organisms Organisms and their environments National Research Council (NRC) National science education standards. Washington, DC: National Academy Press. Student Success At the end of this project, every student was able to read temperatures and explain what a thermometer measured. Most students were also able to organize hatching data into a bar graph. Those with difficulties transitioning from pictographs to bar graphs were assigned tiered working groups (groups in which higher proficiency students act as peer-tutors). All students had pictures in their journals that documented larval morphological changes over time, and students compared their observations to their classmates an experience peppered with comments such as, Where are the gills? or After all that time your eggs are still round? All students were able to respond to the teacher s questions regarding the original prediction and outcome eggs hatch fastest under warmer conditions. All could connect the developmental stages of the salamander to other life cycles viewed in text. Children especially liked this activity because they loved caring for and observing the animals and being able to relate what they had read about to what they actually observed themselves. Not only did students learn the importance of keeping good records, they also found that their records can help them to make informed decisions about environmental conditions that can affect their world. n Theodora Pinou (pinout@wcsu.edu) is an assistant professor and science education coordinator in the Department of Biological and Environmental Sciences at Western Connecticut State University in Danbury, Connecticut. Hope A. Flanigan (hope. flanigan@new-haven.k12.ct.us) is a first-grade teacher, and Marjorie S. Drucker (Marjorie. drucker@new-haven.k12.ct.us) is a magnet theme content coordinator, both at Barnard Environmental Studies Magnet School in New Haven, Connecticut. References Brett, J The umbrella. New York: Penguin. Casteel, C.N Big book math: Let s measure with tools. Waterbury, CT: Abrams and Company. Himmelman, J A salamander s life. New York: Children s Press. Kuhn, D From egg to salamander. Click 10(9): Maaruska, E.J Salamanders. Mankato, MN: The Child s World. Mayer, M Little critters Earth day book. New York: HarperCollins. Mazer, A The salamander room. New York: Dragonfly. Murray, P Science around us: Amphibians. Mankato, MN: The Child s World. National Science Resource Center STC Weather. Burlington, NC: Carolina Biological Supply Company. Willow, D At home in the rainforest. Watertown, MA: Charlesbridge. Internet Resource Enchanted Learning Salamander Diagram Salamanderprintout.shtml January