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Earth’s Energy
Teacher’s Guide
Grade Level: 3-5
Curriculum Focus: Physical Science
Lesson Duration: 1-2 class periods
Program Description
Sources of Energy (5 min.)—Explore why some power is better than others. Electricity (8 min.)—Learn
how we first harnessed the natural force of electricity. Magnetism (6 min.)—See what happens when
atoms take sides. Solar Energy (2 min.) – Find out how solar energy can be collected and used.
Onscreen Questions
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What is energy?
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How many different sources of energy can you name?
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What is the difference between renewable and non-renewable energy sources?
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How do humans rely on electricity?
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Where do people get electricity?
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What is static electricity?
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How does lightning occur?
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Why is it important to understand the properties of magnetism?
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Where do you encounter magnetism?
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What is the relationship between magnetism and electricity?
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What is the function of Earth’s magnetic field?
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What methods are used to collect solar energy?
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What are the benefits of using solar energy?
Lesson Plan
Student Objectives
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Construct a simple circuit, a series circuit, and a parallel circuit.
Life Cycles: Teacher’s Guide
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Demonstrate an understanding of the difference between a series circuit and a parallel circuit.
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Give examples of the different types of circuits they use or have seen being used.
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Materials
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Earth’s Energy video and VCR, or DVD and DVD player
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D-cell battery, 1 per student group
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D-cell battery holder, 1 per student group
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6-inch pieces of insulated wire with ends stripped, 4 per student group
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Small light bulbs, 2 per student group
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Light bulb holders, 2 per student group
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Paper (or science journal)
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Pencils
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Computer with Internet access (optional)
Procedures
1. Review the concept of electricity with the class. How is electricity created? How does it work?
What is an electrical current? How does it travel? How do humans harness electricity from the
Earth? A good way to review this topic is to watch Earth’s Energy.
2. After watching the program, talk about electric current and the different types of circuits. How
do these circuits work? What is the difference between a series and a parallel circuit? Divide
students into groups of 2-3 and have each group make a simple circuit, a series circuit, and a
parallel circuit.
3. Give each group a D-cell battery, battery holder, two pieces of electrical wire, a light bulb, and a
light bulb holder. Give students the following directions to construct a simple circuit:
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Attach one end of one piece of electrical wire to the positive end of the battery holder
(marked with a +)
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Attach the other end of the same piece of wire to one end of the light bulb socket.
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Attach another piece of wire to the other end of the light bulb socket
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Attach the other end of this second piece of wire to the negative (-) end of the battery.
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Screw the light bulb into the socket
The result should look like this diagram.
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4. Ask students to describe what happens to the light bulb when all the wires are correctly
attached. Explain that this is a simple circuit. Have students draw a diagram of a simple circuit
in their science journals or on a piece of paper.
5. Give each student group a second light bulb and light bulb socket and two more pieces of wire
and ask them to think about a way to light both bulbs at once. Have volunteers describe how
they would go about creating a circuit that would light both bulbs at once. Discuss some of the
hypotheses and have students test them out to see if they work. Then, explain that there are two
different kinds of circuits that could be used, a series and a parallel circuit.
6. Use the following instructions to help students construct a series circuit:
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Remove bulbs from bulb sockets, if necessary.
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Attach a wire to the positive (+) side of the battery holder.
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Attach the other end of this wire to one side of the light bulb socket.
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Attach a second piece of wire to the other side of the light bulb socket.
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Attach the other end of this second piece of wire to one side of the second light bulb
socket.
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Attach a third piece of wire to the other side of the second light bulb socket.
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Attach the other end of this third piece of wire to the negative (-) side of the battery.
(There should now be a continuous loop from one end of the battery, through both light
sockets, to the other end of the battery.)
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Screw the light bulbs into the sockets.
The result should look like this diagram.
7. Have students describe what happens to both light bulbs when the circuit is complete. Explain
that in a series circuit, an electric current flows from the battery to one light bulb and then
through to that bulb to another and, finally, back to the battery in one continuous loop, or
circuit.
8. Next, have them hypothesize about what would happen if they loosened or disconnected one of
the light bulbs in the circuit. After writing down their hypotheses, have them experiment with
their circuit to see if they were correct. What happens when one of the light bulb sockets is
loosened or released? Ask students to draw a diagram of their series circuit in their science
journals or on a piece of paper.
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Life Cycles: Teacher’s Guide
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9. Tell students they will next make a parallel circuit. What do they think is the difference between
a parallel circuit and a series circuit? What do they think will happen if they loosen or release a
light bulb in a parallel circuit?
10. To make a parallel circuit, begin with the simple circuit created earlier. (Remove bulbs from
their sockets.) Once this is done, have students use the following instructions to complete their
parallel circuits:
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Attach the second light bulb socket by connecting a new wire from each side of the first
bulb socket to each side of the second bulb socket.
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Screw the light bulbs into the sockets.
The result should look like this diagram.
11. Explain that what they have just constructed is a parallel circuit; the electricity from the battery
flows through two separate branches of the circuit to bring an equal amount of energy to the
two bulbs. Have students compare the diagram they drew of a series circuit with this parallel
circuit. How does the series circuit differ from the parallel circuit? (A series circuit has only one
loop of energy as opposed to the branches created in a parallel circuit.) What do they think will
happen if you loosen or release one of the light bulbs in a parallel circuit? Have student groups
experiment with this and see what they find out. Have students draw a diagram of a parallel
circuit in their science journals or on a piece of paper.
12. After students have demonstrated a clear understanding of parallel and series circuits, ask them
to provide examples of parallel and series circuits they have used or seen being used. Some
possible examples include: strings of Christmas lights (series), hydroelectricity from the Hoover
Dam (parallel), and streetlights (parallel). Finally, discuss direct and alternating currents and
talk about how we measure the flow of electricity.
13. If there is time, allow students to go online and learn more about electricity and electric circuits
at the following Web site:
http://www.andythelwell.com/blobz/ (requires Macromedia Flash Player 6 or above)
Assessment
Use the following three-point rubric to evaluate students' work during this lesson.
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3 points: Students were highly engaged in class discussions; were highly engaged in their
group experiments; correctly constructed all three types of circuits; and were able to
demonstrate an understanding of the differences between these circuits.
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2 points: Students participated in class discussions; participated in their group experiments;
correctly constructed at least two of the three types of circuits; and had the beginnings of an
understanding of the differences between these circuits.
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1 point: Students participated minimally in class discussions; participated minimally in their
group experiments; and correctly constructed one or none of the three circuits; and were
unable to demonstrate an understanding of the differences between these circuits.
Vocabulary
alternating current
Definition: Electric current in which electrons repeatedly change direction
Context: The electricity current found in most buildings is alternating current.
ampere (amp)
Definition: Unit of measurement used to determine the amount of electric charge flowing past a
given point each second.
Context: Trying to send too many amps through a circuit can cause a fire.
conductor
Definition: A material through which electric current flows easily
Context: Copper, aluminum, and iron are all good conductors of electricity.
circuit
Definition: The complete path of an electric current
Context: When an electric circuit is broken the current stops flowing.
direct current
Definition: Electric current that flows in one direction only
Context: Batteries produce direct current.
insulator
Definition: A material that opposes the flow of electric current
Context: Rubber, glass, and plastic are all good insulators.
voltage
Definition: The force that drives electrical charges through a circuit
Context: As voltage increases, so does the flow of energy.
Academic Standards
National Academy of Sciences
The National Academy of Sciences provides guidelines for teaching science in grades K–12 to
promote scientific literacy. To view the standards, visit this Web site:
http://books.nap.edu/html/nses/html/overview.html#content.
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This lesson plan addresses the following national standards:
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Unifying Concepts and Processes: Change, constancy, and measurement
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Science as Inquiry: Abilities necessary to do scientific inquiry
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Physical Science: Light, heat, electricity, and magnetism; Transfer of energy
Mid-continent Research for Education and Learning (McREL)
McREL's Content Knowledge: A Compendium of Standards and Benchmarks for K-12 Education
addresses 14 content areas. To view the standards and benchmarks, visit
http://www.mcrel.org/compendium/browse.asp.
This lesson plan addresses the following national standards:
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Science: Physical Sciences—Understands the sources and properties of energy
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Science: Nature of Science—Understands the nature of scientific knowledge; Understands
the nature of scientific inquiry
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Language Arts: Viewing—Uses viewing skills and strategies to understand and interpret
visual media
Support Materials
Develop custom worksheets, educational puzzles, online quizzes, and more with the free teaching tools
offered on the Discoveryschool.com Web site. Create and print support materials, or save them to a
Custom Classroom account for future use. To learn more, visit
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http://school.discovery.com/teachingtools/teachingtools.html
Published by Discovery Education. © 2005. All rights reserved.