Lesson 6: Analyzing historical data to establish trends (1-2 periods)
SPI Inq.3 Interpret and translate data into a table, graph, or diagram.
Inq.4 Draw a conclusion that establishes a cause and effect relationship supported by evidence.
Adapted from need.org lesson plan Energy Analysis for intermediate grades.
Students will translate historical data from a table into a graph to establish trends in energy consumption and production, and factors that contributed to the trends in consumption and production.
Students should be able to answer the following questions:
•How has per capita consumption of energy changed in the last 60 years?
•How has the rate of production changed in the last 60 years? How does this compare with the rate of consumption? Does this look or sound right to you? Why or why not? Assuming this is actual valid data, what are some questions we could research to figure out what has happened?
•How has the mix of energy sources changed in the last 60 years in terms of production and consumption in regard to fossil fuels, uranium (nuclear) energy, and renewable energy sources?
Introduction – Learn from the past to be prepared for the future
Ask students what they think it means to learn from the past. Ask them if they have any examples of how they have used lessons from the past to make better choices.
Continue the discussion by asking students a few questions about puppies and dogs.
1. Do puppies eat the same amount in one sitting of food as full-grown dogs? (Students should say no, that puppies are smaller and cannot hold as much food as an adult dog can.)
2. How often would you have to buy food if you had 1 dog? 5 dogs? 10 dogs? Let’s ignore that there are different sizes of food bags out there and pretend that there is only one standard size for all food bags. You will most likely have at least one student that will want to know how big the bag is and how much food the dog will eat each day. The dogs will eat 2 cups of food a day each and the bag holds ~60 cups of food.
3. There are four types of food on the market; they are all the same size. All dogs eat the same amount, 2 cups. What would happen to the demand if the total number of households with one dog increased and the number of households with more than one dog increased? What would need to happen in order to meet the demand?
4. What would happen to the resources used to make the dog food?
Okay, we have been talking about dogs and the effect that increasing the number of houses with dogs and the number of houses with more than one dog would have demand for resources. If nothing is done to meet the demand then dogs will go hungry or somebody will have to come up with an alternative solution for feeding the dog. But even alternative solutions have consequences that have to be considered in both the short and long term.
Activity (Explore and Explain combined)
Transition to the Now we are going to look at some historical data regarding energy consumption and production. Our first task will be make graphs using the information in the data tables. Once we have the data tables made we can analyze the data and draw conclusion about what has happened over the past 60 years (trends) and provide possible explanations for why these trends have happened.
Do the first graph with the students, explaining which type of graph you will use and why that is the best graph to use, how to set up the graph and plotting the information. Then, using the graph, help students use the graph to answer some questions, such as:
-What years had the least amount of increase in energy consumption? What about the slope of the line between those years compared to the other years indicates that the amount of energy increase was lowest during that time?
-Compare the slope of the line between these same years for population growth. Is there any significant difference between this slope and the slope of the other years?
-What are some possible explanations for why there was little to no change in population growth but there was significant change in energy consumption? (Students may not be able to come up with any answers to this question. This is to get students thinking. Some possible explanations they may come up with are: improved technology, better insulation, environmental changes, more awareness in conserving energy, changes in economy resulting in people changing habits, etc.)
Ask additional questions until you are confident that the students are able to use the graph to answer questions related to that data.
Have students answer the first of the three assessment questions before moving on to the next data set. Circulate the room to assist where needed and assess student progress in evaluating graphs. Ask for some volunteers after students have had sufficient time to construct their answers.
Set up the second graph for students but have the students plot the data on the graph themselves. Be sure to emphasize what information should go on the Y axis and X axis, this will help when teaching students about independent and dependent variables. Once students have plotted their data go through some practice questions using this data. Then have the students answer the second set of questions:
How has the rate of production changed in the last 60 years? How does this compare with the rate of consumption? (Students may not fully understand what is meant by consumption and production of energy at this time. This is a great opportunity to help students use data they are unfamiliar with to answer questions in preparation for the Explore science test.) Does this look or sound right to you? Why or why not? Assuming this is actual valid data, what are some explanations for this set of data?
Exploring Energy consumption by sector:
Ask the class: What is meant by “consumption”? Who/what consumes the energy? Does this consumption change or is it always the same?
HW assignment: maintain a log of all the activities and items they use that uses electricity for 1 week.
Hand out information from the need.org website Intermediate Energy Infobook about consumption (pgs 46-50). You could jigsaw this part and have students become experts in one area of consumption that they will teach to their group partners. Step 1 – student becomes expert in 1 area of consumption. Reading and making notes about key information (provide scaffolding/guiding questions as needed). Step 2- Expert Groups: students get with other students who read the same information. The group collaborates to come up with the information they will use to teach others about their sector. Step 3 – one student expert from each are of consumption will be in a group. Each expert will teach the others in their group about their area of consumption. Students will take turns teaching each other about their sector. Student will either complete a graphic organizer or take notes, depending on the level of your class.
In small groups return to the second data table and questions. Now that you have a better understanding of “consumption” review your responses and make revisions to your answers.
Extension: peak hours
Ask students to think about the typical weak day. What times of the day do they think the most energy is consumed? Why? What seasons do you think might have changes in the amount of energy consumption? Why?
Give students the topic for the third graph: energy production by source. Ask students how many sources are included in the data table. Ask students which type of graph they think would be the best to use (line, bar, pie) in this situation (the line graph). Ask them how many different lines there should be on the graph. Show students how to differentiate the lines so that whoever is using their graph will know what each line represents. Have students complete this graph and do the fourth graph with a partner. Have students use their graphs to answer the following questions:
•How have the different energy sources (fossil fuels, uranium (nuclear) energy, and renewable energy sources) changed in the last 60 years in terms of production and consumption? What are some possible explanations for this change in the mix of energy sources? (Hint: what are fossil fuels? Where are fossil fuels found? How do we get those fossil fuels and what happens when they are burned? What are renewable energy sources? What are the benefits of renewable energy? What are the challenges regarding the use of renewable sources for energy production? This last question is tying back in to an earlier lesson where students studied maps of the power grid, types and locations of plants, locations for solar and wind power plants, and locations of the majority of the US population. Some answer are: inconsistencies in solar and wind, storage, locations for solar and wind plants, transmission to areas where solar and wind are not good options – earlier lesson?
Additional resources for graphs and data that could be used
http://www.eia.gov/todayinenergy/detail.cfm?id=11951
http://geology.com/articles/history-of-energy-use/
http://ourfiniteworld.com/2012/03/12/world-energy-consumption-since-1820-in-charts/
Formative assessments: class discussions and completion of the last two graphs and corresponding questions.
Summative assessment: students will translate data from a table into a graph. Students will analyze data tables to answer questions.