Judith S. Goodrich
Preparing for research
Now that the overview of the unit is laid out -- itt’s time to talk about the specifics. How do I take a classroom of students who think that the colonists kept cool with electric fans to a group of students who know how a steam engine works and how it influenced change in American society? The notion of change and development over time is difficult for 8th graders to grasp. Combining the goal to guide students to think critically about the positive and negative aspects of progress with the objective that students understand the concept of energy and how an engine works will be a challenge. Therefore, the unit will begin with a very structured framework before students can move to individual (team) research.
We will begin by developing some basic definitions and creating a useful glossary of important terms and concepts. The students’ understanding of this ‘vocabulary’ should be reflected in their final performance task by their using the words in the reports -- students also will encounter many of the terms in the course of their research and so a glossary will be helpful. More terms can be added as questions arise or as students discover other essential words or phrases. The teacher resource list contains books and websites (some interactive) that explain many of the basic terms in great detail and in varying degrees of complexity. The class will create a word wall of the terms and their definitions that will be accessible throughout the unit. The key terms to be used in the unit are energy, work, heat and heat engine.
Energy is the ability to do work or the power we use to do things. The kinds of energy include heat (thermal), light (radiant), mechanical, electrical, chemical, and nuclear energy. There is stored or potential energy (chemical) or working energy (mechanical and kinetic) energy. The sources of energy are renewable (solar, wind, hydropower) and non renewable (fossil fuels and uranium). The class will discuss these ideas and come up with practical examples to demonstrate their understanding. We will relate the idea of fuel and energy to their eating of a good breakfast and the energy they have (or don’t have) to do work throughout the day. We will talk about the furnaces in their homes and apartments and the kinds of cars their families drive -- what fuels are they using and where do they come from?
Work is the force acting upon an object to cause displacement or movement across(up or down) a distance; it is written in an equation as W = f x d (work equals force times distance). Again we will think of examples of work beginning with the example of someone pushing against a wall and going nowhere. We will talk about why the definition of work was created.
Heat is a form of energy transferred by a difference in temperature; thermodynamics is the study of heat and how it changes into energy. There are laws that describe how this transfer happens and for this unit we will look at the first and second laws of thermodynamics.
Heat engines change heat energy into mechanical energy. Some examples of heat engines are steam engines, steam and gas turbines, spark-ignition and diesel engines, and the Stirling engine. These heat engines can provide power for transportation, can be used to operate machinery, or can produce electricity. I chose heat engines as the focus for the unit because they affected so many areas of urban (and rural) development. The students should be able to find a variety of such engines at work in their chosen cities.
A heat engine6 uses energy from heat to do work, but not all the heat can be used for work because heat engines are not 100% efficient. A heat engine exhausts the heat that isn’t used for work -- a more efficient heat engine might find a way to use some of that exhausted heat to provide some other use. For this unit most of the students will be looking at the use of the steam engine. The steam engine, like all heat engines, cannot use all of the heat to do work because no engine is completely efficient. The students should be able to understand that the hotter the steam is and the colder the air into which the steam is ‘dumped’ is, the more efficient the engine will be. I think the concept of efficiency is important to introduce to the students because it helps drive the quest for more innovation in the world of engines -- a more efficient engine produces more power and ‘wastes’ less fuel; and a less efficient engine needs to do something with the energy not converted into work, and in many cases this becomes pollution.
Once the class has discussed and been confused by these many ideas and definitions -- we will view some short video clips about energy, engines, fuel and work. We will read Unit 10 -Chapters 1-3 in the textbook
Exploring American History
and talk about the United States becoming an industrial nation after the Civil War. The chapters highlight changes in transportation from the canal system to the use of steamboats and rail systems in the second half of the century. Spinning machines, power looms and mechanical reapers are mentioned, as are changes in industries that rely on iron and steel production. Discussion of turbines, dynamos, oil refineries and the Bessemer process will introduce students to a range of possibilities for their individual topics. As we spend time on the textbook readings we will add other ideas about what to look for when researching change in the different cities during the Industrial Revolution. We will relate the content of the text to our definitions and frame our reading of the text along the lines of development, progress, and the changing American environment.
The cities that we will use for the research have been pre-selected. (Figure 2) I have checked online for each city to make sure that historical material is available and that a significant heat engine of some sort was used in that city in the 19th and early 20th century. When the students select their cities, they will be choosing from a list of longitude and latitude coordinates -- I want to avoid the studentt’s ‘vying’ for cities and use the opportunity to review some geography skills. Most of the cities developed around the railroad with the establishment of particular lines running different types of steam locomotives. Steam powered electric plants are found in several locations; factories using gas and steam engines seem easiest to find in the steel industry centers of the east. Lumber, grist, and textile mills were powered by steam, and even the cable cars of San Francisco and Omaha! Cities by the great American rivers rely on steamboats -- and almost all of the above heat engines can be found in New York City.
Once the students have identified their latitude and longitude locations as actual cities, they can begin their research. The students are set free to begin to answer the essential question
Is the history of the growth of a city a history of progress?
Before students can move to the Internet or to resources in the classroom, they must compile a list of questions to guide them in their research. In essence I am following the “Big Six” school of research that outlines a Six Step approach7. Bob Berkowitz, the man behind the Big Six ideas, has developed a very useful website that is fine-tuned especially for specific grade level students.8 The process of research is outlined at this site -- beginning with the idea that the student must think about what he is looking for before beginning the quest. We will follow this process in the unit and students will need to write out some initial questions before moving out to the World Wide Web -- or to the encyclopedia, or to the library text, to find information.
Any significant source of information must be documented by the students: proper citation formats will be visible around the room on charts -- for images, websites, books, encyclopedia articles -- so that the student can record references correctly. Again, the idea in this exercise is to instill the recognition that organized information, like many other things, belongs to the people who have done the work. Students need to learn to give credit where credit is due.
I hope to spend some time discussing pollution and the heat engines that directly touch the lives of the students i.e. the internal combustion engine as used in automobiles. Almost every student can relate to a trip to the gas station and the rising costs of filling a tank. They know from experience that an SUV will use more gasoline than a small compact car. The students also know about and many have experienced lead poisoning -- which seems a perfect example of a serious pollution problem created by heat engines that was regulated by public policy when lead was removed from gasoline. Students need to realize that individuals and their governments can act to decrease the negative effects of the heat engines so important to our thriving societies.
Many of these current issues can become the focus of homework after we have discussed concepts and terms in class. The homework for the unit will bring the students back to the 21st century and will direct them to think about the effects of heat engines (especially gas combustion engines) on the environment. Students will read excerpts and look at charts and graphs from current news articles and magazines about relevant topics including gas prices, oil reserves, alternative heat sources, and global warming. We will talk about the homework assignments, both before and after the assignment is completed. These charts and graphs can be found in many of the resources in the bibliography and can be reproduced for classroom use. As the topics of fuel cells, hybrid cars, high oil prices and nonrenewable fuel supplies become increasingly mentioned on the news and in major newspapers, teachers and students can keep an eye out for current material to use in class. A possible homework assignment could also be to have students keep a running record with summaries of news articles and radio and television reports on the topic of pollution, the environment and fossil fuel issues that they encounter over the course of the unit.
Classroom lessons
In the lessons that follow, it should be apparent that I am integrating some science in the social studies classroom, because I believe the demonstrations of how things work -- how energy makes things happen -- should help the students see that they CAN understand how things work in the physical world. It is possible for an 8 8th grader (and his teacher for that matter) to understand how technology has been ‘invented’ and improved upon by people willing to experiment, to think, and to apply common sense. The world is knowable…or at least parts of it. When the students move to the historical research on their topics, I want them to wonder how the machines, or engines, or moving parts actually work and understand that science and history and other curriculum areas overlap.
I think the students will enjoy seeing some actual engines in operation. The test tube Stirling engine was made from a kit ordered online9 and it shows how the exchange of hot and cool air can cause repeated movement. I also hope the students will grasp how this very simple heat engine can work -- leading perhaps to a better understanding of more complicated engines that they encounter during their research, such as the steam powered looms, trains, pumps, and steamboats. I will show a homemade crank-wheel boat that uses a wound up rubber band to power itself through the water. The boat also demonstrates other types of energy -- mechanical, kinetic and potential (human muscle power). We will keep talking about work (work equaling force times distance) as the engines are demonstrated. The putt putt boats which the students will create in small groups will lead the class into a discussion of steam power and will serve as a reference point over the course of the unit when we need to revisit and clarify terms about heat or types of energy, steam power, or work.k.
Activity One: Webquest on Energy
Grades: Grades 7-9
Guiding Question: What more can we discover about energy to help us review and enrich what we have discussed in class?
Performance Task: Students will complete a graphic organizer that requires them to rewrite definitions of basic terms and find examples.
Social Studies Performance standard: Demonstrate understanding through written, verbal, visual, and/or technological formats
Objectives:
-
Students will review vocabulary terms: energy, types of energy and work
-
Students will identify renewable and nonrenewable sources of energy
-
Students will identify an individual who was a pioneer in the field of energy
-
Materials: Computers, webquest guide-graphic organizer
Schedule: One block length class period
Procedure: This webquest will be scheduled after the class has spent time together working on definitions and terms. I will identify the websites I want the students to use and will list them in a folder titled
Energy
in the favorites menu. Students will receive a graphic organizer (this worksheet is also available digitally) that will direct them to look for specific information that can be found at the websites. Students will move through the questions to complete the worksheet. The worksheet will include open-ended questions so that students who finish before the end of the class period will be able to work on a task in more detail.
As part of the webquest students will look at an online video clip on energy titled
Adventures in Energy10
This website was developed by the Oil and Natural Gas Industry and the video does a good review on the meaning of energy. The video will introduce a historically oriented lesson on energy, the forms of energy that people and machines use and the strategies of early thinkers whose work made it possible to measure energy and the heat and work that it produces. Students can investigate specific individuals at another website all about the ‘pioneers’ of energy. Students will be directed to go to another energy site to look at some examples of types of energy at work11.
Assessment: Students will save their completed graphic organizers to their digital portfolios and print out a hard copy. I will review their answers which we will discus as a class in the next class. Students will be quizzed on the meaning of energy, work, and sources of energy and types of work.
Activity two: Let’s Look at Some Engines!
Grades: 7-9th Grade
Guiding Question: How do engines do work?
Performance Task: Students will create a simple engine, make predictions, demonstrate it, and reflect on the experience in an essay using appropriate vocabulary.
Social Studies Performance Standards: Students will formulate questions and hypotheses from multiple perspectives.
Objectives:
-
Students will create a simple heat engine.
-
Students will analyze a simple engine that they have created by predicting, observing, and reflecting.
-
Students will use vocabulary correctly and write a response essay
-
Students will understand the meaning of work
Materials: Copper tubing in 10-inch lengths (8), tea candles (8), plastic, foil, and cardboard materials for making a boat, glue, water table or large container to float the boats.
Schedule: We will use a block period to look at a Stirling engine demonstration and a flywheel rubber band boat demonstration before the students use the rest of the period to make their boats. We will work with the science teacher to use the following science class to test the boats and discuss what the class learned.
Procedure: The class will be divided into groups of three or four students each. Each group will receive copper tubing, the tea candle (no matches), and access to materials to select from for making a boat. Students will have access to a container of water to test whether their boats can float.
Students will make predictions about what will happen when the boats are tested with the candle in the water and will try to explain what happens. Students will be asked to describe how the boat will show the meaning of work.
Assessment: Teacher will observe group interaction; the group will hand in their predictions and explanations; students will write up a short essay describing what they have learned after the boats are demonstrated and the class has discussed results.
Activity three: Homework on Oil Consumption in the US
Grades: 7-9th Grade
Guiding Question: How does the way an American drives affect the consumption of oil?
Performance Task: Students will answer questions based on their reading of a chart and a short news article. Students will write a short response essay.
Content Standard 4.0: Assess the impact of technology on the global economy.
Objectives
-
Students will analyze charts and graphs
-
Students will use information from charts and graphs to write an essay
-
Students will understand the connection between driving habits and fuel consumption.
Materials: Handout of the
New York Time’s
Article “Growing more Oil Dependent one Vehicle at a Time” by Dylan McClain, 2004. Teacher developed worksheet with questions and assignment.
Schedule: One night homework assignment
Procedure: Students will read the article, review the charts and graphs, answer the worksheet questions and write a short essay. The class will review the homework the next day.
Assessment: The essay and worksheet answers will be used as assessment.