Unit Topic: The Galapagos Islands
Grade Level: Middle School
Basic Concepts: Prediction, Data Analysis, Graphing
Content Areas: Science, Geography, Social Studies, Math
Time: 2 1/2 hours (interspersed with Literature Circles)
Phase 1: The teacher will begin a discussion on island climates by asking students what they already know about the topic. List the students' ideas on an overhead. Do the students believe that most islands have warm or cool climates? The teacher should ask the students to venture an opinion as to why the climate is either warm or cool.
Materials: overhead projector, blank transparency
Phase 2: Next, the students will conduct an experiment to determine the heat capacity of water versus air. Heat capacity is the amount of energy a substance can hold. Students will work in groups of four. Each group will fill two small jars with water at room temperature and leave two other jars "empty" with air at room temperature. Each group will place one jar of water and one jar of air in a cool, shaded place. The other two jars (one of water and one of air) will be placed in direct sunlight. Students should measure the initial temperature of their substance and record it on their data sheet. Then ask students to make predictions on their data sheet. What do they think will happen? Which jar will be the warmest? Which jar will be the coolest? [Note: Phase 1 and Phase 2 up until this point will take 45 minutes.] For the next hour, students will take temperature readings at 15-minute intervals, always recording the temperature on their data sheet. [During this time students will be working in their literature circle group.]
Materials: Each group will need four small jars and one thermometer, water, and a data sheet.
Phase 3: Each group will then compile their data and graph their results. Two separate graphs are needed, one for water and one for air. Temperature should be placed on the y-axis and time should be placed on the x-axis.
Materials: data sheets, graph paper
Phase 4: Using their graphs, the students will draw conclusions about the heat capacity of air and water, and share them with the class. How does the heat capacity of a substance reflect the climate of a region? How can this experiment be connected to the climate of the Galapagos Islands? What conclusions can be drawn about the climate of the Galapagos Islands? The teacher may wish to share exact information about the climate of the Galapagos. [Note: Phase 3 and 4 should take about 45 minutes.] Teacher Explanation: Water has a higher heat capacity than air. It takes much more energy to change the temperature of water than that of air. Water warms and cools much more slowly than air. Hence, temperatures of coastal or island regions tend to remain more constant than the temperatures of inland regions because they are "insulated" by water. This explains why the Galapagos Islands maintain a relatively constant climate.
Materials: graph
Phase 5: After the class discussion, students will complete the "Results" and "Conclusions" section of their data sheet. Be sure to let students know that these two sections will be evaluated.
Materials: data sheet
Several hundred years ago climates were not as fully understood as they are today. Using primary sources, students will research early accounts of how people explained climate and temperature. Did they use scientific reasoning? Were there particular legends that explained climate? Students will informally share the results of their research with the rest of the class.
Assessment: Students will be assessed through peer review. A successful student will receive all two's and three's on the peer review rubric. See the following rubric.
Students will also be evaluated on their responses to the "Results" and "Conclusions" section of their data sheets. The teacher should use his/her discretion for this part. Reasonably "correct" responses will receive a plus, while responses that seem unjustified or out of context will receive a minus. A successful student will receive two pluses. If a student receives a minus, he or she will have the option of rewriting their response, after meeting with a peer or the teacher for further discussion of the experiment (refer again to Phase 4). This will ensure that no student will necessarily fail the assignment.
Extensions:
Resources:
Smithsonian Institution. (September/October 1995). Art to Zoo: Teaching with the Power of Objects. Tomorrow's Forecast: Oceans and Weather.
Other Suggested Resources (*denotes "youth-friendly"):