Energy Unit Explain that when energy is transferred from one system to another, the total quantity of energy does not change.

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1 Energy Unit This unit was prepared for middle school students who are lower ability or are far behind in their education due to behavior issues. With my students, this unit will take about two weeks to complete. There are many ways in which these activities can be adjusted to make them meet the needs of students at many other levels. Outline for Unit: Day #1: Activity #1, steps 1-5 Day #2: Activity #2 Day #3: Work day for Activity #1 Day #4&5: Activity #3 Day #6: Work day for Activity #1 Day #7&8: Activity #4 Day #9: Work day for Activity #1 Day #10: Activity #1, steps 6-8 Indiana Standards addressed: 7 th Grade: Explain that when energy is transferred from one system to another, the total quantity of energy does not change Describe and give examples of how energy can be transferred from place to place and transformed from one form to another through radiation, convection and conduction Recognize and explain how different ways of obtaining, transforming, and distributing energy have different environmental consequences Understand that energy is the capacity to do work Explain that energy can be used to do work using many processes, for example generation of electricity by harnessing wind energy.

2 8 th Grade: Identify, explain, and discuss some effects human activities have on the biosphere, such as air, soil, light, noise and water pollution Recognize that some of Earth s resources are finite and describe how recycling, reducing consumption and the development of alternatives can reduce the rate of their depletion Explain that human activities, beginning with the earliest herding and agricultural activities, have drastically changed the environment and have affected the capacity of the environment to support native species. Explain current efforts to reduce and eliminate these impacts and encourage sustainability Investigate the properties (mechanical, chemical, electrical, thermal, magnetic, and optical) of natural and engineered materials.

3 Activity #1 The Power Plant Dilemma The students are residents in a town in need of replacing their aging coal burning power plant. They will research a form of renewable or nonrenewable energy and present it to the city council so that the council can make an informed decision on how to resolve this problem. Materials Handouts and overhead transparencies Background 1 per student and 1 overhead transparency Student Information Page 1 per student Power Plant Option page 1 per student How Would You Vote page 1 per student Optional - poster board (Cost ~66-99 each) Procedures 1. Display the scenario on the overhead projector and read through the description with the class. (the Background ) 2. Divide the class into partners or small groups of students. Distribute copies of all three handouts and go over directions/expectations. 3. Start the group/partner discussions by suggesting that students begin by sharing what values and priorities they think should guide the council s decision. 4. Reconvene as a class for discussion: What values are most important to you in choosing these options? Why did you choose these values? (Expect a variety of answers. Some may value attracting business so that the town will experience economic growth. Some may value environmental quality above all other things.) 5. Allow the students time to research their topic and complete the other unit activities. Students will have 3-4 days of true research and presentation preparation time. (This part of the unit can also be assigned as homework instead of using class time.) 6. Hold a council meeting during which each group/partners present their options to the council. 7. As a class, discuss: What trade-off or opportunity cost did you expect for each option? ( focus on changes in the costs and benefits) Who is very pleased with their final choice? 8. Allow approximately minutes for a brief assessment in which students write paragraphs explaining how they would vote as members of the council and why. Their explanations should include a statement of the values that drove their decisions and of the trade-offs (costs and benefits) they re willing to accept. (See How Would You Vote?)

4 Background Our town s coal burning power plant is almost 30 years old and is need of repair. Most coal burning power plants can only be used for years before they need to be retired. The power plant provides jobs for 115 people that live in our town. Our town relies on the income from the surrounding towns that buy their electricity from the power plant. This money helps to pay the police, firemen, and EMTs that help to keep us all safe. Paisley Industries, a 400-employee clothing company currently headquartered in New York, has agreed to relocate to our town. Completion of the Paisley headquarters and relocation to our town is scheduled for 18 months from now. The opening of the Paisley headquarters is expected to immediately create 100 jobs in our town. Paisley has asked for periodic reports and has made it clear that construction of the headquarters will stop unless evidence of progress on a new power facility in our town is provided in the near future. When she learned of the negotiations between Paisley and the town council, the owner of Addison Builders purchased a large tract of land on the outskirts of our town and has begun construction of a moderately-priced subdivision. She has already completed the infrastructure and is on schedule to finish the homes so that they will be ready for Addison employees when the new headquarters is finished.

5 Student Information Page Online Resources: Science sites pg69_potential.html g126_coaster.html _pg101_kintheory.html General Area Report on your options Prepare a presentation on the option you have researched. It may be either a poster(s) or you can create a set of slides in a PowerPoint presentation. Include in your report: An explanation of your option. (10pts) The values that your site matches. (5pts) The benefits of the chosen option. (10pts) o This is like the pros, what facts support this option. The cost of the chosen option. (10pts) o This is like the cons; explain what concerns some people may have with this option. A statement of why the benefits are worth the cost.(10pts)

6 POWER PLANT OPTIONS 1. New coal burning plant 2. Wind farm 3. Natural gas plant 4. Solar panels added to rooftops 5. Nuclear power plant 6. Do nothing

7 How Would You Vote? Suppose that you are a member of our town council. Which of the power plant options would you support? Prepare a brief (1-2 paragraphs) press release explaining your vote. Your explanation should include identification of the values that drove your decision and an explanation of the trade-offs (costs and benefits) you are willing to accept (or impose) on behalf of the townspeople you represent. (This is worth 10pts towards your grade)

8 Activity #2 Energy Scavenger Hunt Students work individually at their own pace to complete the scavenger hunt questions. They do this by visiting the provided websites and finding the answers within the information provided on each site. Materials Scavenger Hunt handout 1 per student Computers 1 per student Completion Certificate 1 per student who successfully answers 60% or more of the questions. (or see attached pdf file) Activity #3 Solar Trek Students will assemble a solar car and then explore how different amounts of light affect the ability to use solar energy. Materials Sunnyside Up car kit ($20 each from SunWind Solar Industries) Scissors Meter stick Stopwatch Light to power car Cardstock squares (~$3 and up for a pack) Blank overhead transparency squares Vellum squares (~$5 and up for a pack) Optional Cellophane squares of different colors (~$2 a roll) Procedures 1. Ask students to brainstorm places that they have seen solar energy used. (Some may mention road signs or calculators) 2. Divide students into groups of 2-3 kids. 3. Distribute Student handouts and go over directions. 4. Students will then assemble cars and test the affects of the three different types of material on the car s motion. (It may be best to cut the squares of material ahead of time.) 5. Afterward, compare the results from each group and discuss what they found. Groups should see that the more light that reached the solar panel, the faster the car traveled and if no light got through the car didn t move at all.

9 Name: Solar Trek Student Page Class: Question: How does the amount of light affect your ability to use solar energy? Procedure: 1. Assemble you solar car by following the directions included with the kit. 2. Use the light and practice driving your car. 3. Mark a starting line on the floor and then measure a distance of three meters and mark the finish line. 4. Time how long it takes your car to travel from the start to the finish and record it in your data table. 5. Run two more trials and record the average time. 6. Next, cut a square of the card stock that is large enough to cover the solar panel on your car. 7. Run three trials with the cardstock covering the solar panel and add you data to the table. 8. Complete trials for each of the types of material provided by your teacher. Type of Material Time It Took the Solar Car to Travel 3 Meters Time (s) Trial #1 Trial #2 Trial #3 Average

10 Analysis: 1. What happened to the car when you covered the solar panel with each type of material and why do you believe it happened? 2. Why did you run trials for the car by alone before covering the solar panel with the different material? 3. What conclusions can you draw about solar power based on this activity?

11 Activity #4 Blades in the Wind Students will create and test three different types of blades for a wind turbine. They will compare these blades by timing how long it takes the blades to wind up 3 meters of string. Materials KidWind Basic Wind Kit ($97 from Vernier) Additional wind turbine hubs ($7 each from Vernier) Additional blade pitch protractor ($4 each from Vernier) Additional blade materials (~$40-50 each from Vernier) Scissors Hot glue Masking tape Wire or paperclips 3 meters of string with nut tied to end Stopwatch Regular box fan Optional sandpaper and utility knife Procedures 1. Before class set up a testing station by setting up the turbine base and setting the box fan in an elevated position 1 meter away from the turbine stand. Also cut the string and tie the nuts onto the end. 2. Show students a video of how a wind turbine works Distribute Student data sheets and explain that they will be using the materials provided to design and create three different sets of turbine blades. a. Remind them to be careful in the lab and anyone needing to use the hot glue should come to you for supervision. b. Once they are happy with their design, they should go to the testing area and run their trials. Everyone needs to be patient and wait their turn. 4. Allow students to work on the activity. 5. Discus with the class which designs worked the best to quickly wind up the string and how they could make improvements to their designs.

12 Name: Blades in the Wind Student Sheet Class: Question: Which blade design allows a wind turbine to spin the fastest? Procedure: 1. Design and create a set of turbine blades. Remember to be safe in the lab and let the teacher know before using the hot glue gun. 2. When ready to test your 1 st set of blades, attach a wire are to the front of the hub for the string to wind around. 3. To test your turbine, attach hub to the stand and use the fan set on medium. 4. Record the time it took to wind the string for all three trials and calculate the average. 5. Create two additional types of turbine blades and repeat testing for each. Blade Version Time It Took to Wind the String Time (s) Trial #1 Trial #2 Trial #3 Average

13 Analysis: 1. Which design worked the best? 2. Which design worked the worst? 3. If you where to design another set of blades, which features would you use from your three designs?