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Electricity and Magnetism, Part 1
Rationale: According to the California State Science Content
Standards, electricity and magnetism are important concepts for 4th
grade students.
Disclaimer: Some of the procedures for the activities contained in the
lessons have been adapted from various resources listed throughout the
module.
Part 1A: Electric Current
introduces ideas of electric current from the microscopic and macroscopic points of view
Activity Summary:
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Introduction
Parts of the atom
Simple series circuit
Microscopic view of circuit
Conductors and insulators
Conductivity test
Experimental conclusions
Special materials
Part 1 Worksheet Item 1
Part 1 Worksheet Item 2
Part 1 Worksheet Item 3
Part 1 Worksheet Items 4 and 5
Part 1 Worksheet Item 6
Part 1 Worksheet Items 6 and 7
Part 1B: Static Electricity
introduces idea of static electricity
Activity Summary:
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Electroscope
Charging balloon
Balloon/string experiment
Balloon/electroscope experiment
Review
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Page 1
Electricity and Magnetism, Part 1
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Part 2: Magnetism
introductory explorations with magnetism
Activity Summary:
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Preliminary observations with magnets
Introduction of magnetic poles, field lines, and force
Magnetic field line visualization
Test for magnetism
Permeability test
Magnetic domains
Magnetize an object
Problem: how to determine the N end of a magnet
Part 2 Worksheet Item 1
Part 2 Worksheet Item 2
Part 2 Worksheet Item 3
Part 2 Worksheet Item 4
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E&M_doc_2
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Part 3: Connecting Electricity and Magnetism
begins to connect electricity and magnetism
Activity Summary:
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Determine N pole of a magnet
Observe magnetic force caused by current
Use current induced magnetic force to do work
Make an electromagnet
Observe current induced magnetic force directionality
Review
Part 3 Worksheet Item 1
Part 3 Worksheet Item 2
Part 3 Worksheet Item 3
Part 3 Worksheet Item 4
Part 3 Worksheet Item 5
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E&M_3_doc
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Part 4: Electricity, Magnetism, and Work
applications of electricity and magnetism
Activity Summary:
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Observe current induction by moving magnetic field
Investigate parameters for changing induced current
Complimentary behavior – speaker experiment
Build motor
Generate electricity
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E&M_4_doc
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E&M_4_wksht
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Part 4 Worksheet Item 1
Part 4 Worksheet Item 2
Part 4 Worksheet Item 3
Part 4 Worksheet Item 4
Electricity and Magnetism, Part 1
Part 1A: Electric Current
Objectives:
After participating in the program Electricity and Magnetism, Part 1A,
students will be able to:
 assemble a simple circuit using insulated wires, battery, small
light bulb, and bulb holder
 explain that electrons traveling through a completed circuit
constitute an electric current
 recognize that electrons travel readily in some materials and do
not travel in others
 test materials and classify them as conductors or insulators
 list several uses for conducting and insulating materials
Vocabulary:
circuit - a complete path over which current may flow
open circuit - an electrical circuit that is broken and thus carries no
current
closed circuit - an electrical circuit that is complete and can carry a
current
electron - an elementary particle found in all atoms (not in the
nucleus) which carries a negative charge
proton - an elementary particle found in the nucleus of all atoms
which carries a positive charge equal to the negative charge of
an electron
neutron - an elementary particle found in the nucleus of all atoms
which carries no electrical charge
conductor - a material through which electricity can readily flow
insulator - a material through which electricity cannot readily flow
Lesson Plan:
Materials:
For each group:
 3 sets of insulated wires (with alligator clips)
 6 V battery
 light bulb and holder
 bag of test materials (glass, magnet, washer, marble, Al foil,
eraser, nail, rubber band, penny, screen, sponge, wood,
plastic, pencil lead, etc.)
 bag of special materials (ITO coated glass, diode, LED,
conductive polymer)
For each student:
 worksheet
Time:
activity 1:
activity 2:
activity 3:
activity 4:
activity 5:
activity 6:
activity 7:
activity 8:
5 minutes
5 minutes
10 minutes
5 minutes
10 minutes
5 minutes
5 minutes
5 minutes
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Electricity and Magnetism, Part 1
Activities:
1. (5 minutes)
 Have students sketch on their worksheets, two items they used
today that run on electricity.
 Briefly take survey of the students to see how many different
items they listed.
2. (5 minutes)
 Ask the students to identify the parts of the atom and the
charges of the various particles on their worksheets. If they have
not yet studied the atom, you may want to skip this or simply
show them the parts of the atom.
3. (10 minutes)
 Have students work in groups of 3 or 4, depending on how the
room is set up.
 Hand out boxes containing the bulbs, batteries, wires, and the
bag of test materials.
 Ask students to make the bulb light. There are several ways to
make this circuit so have them use two wires, the battery and a
bulb in its holder.
 Ask students to draw on their worksheets the circuit they made.
 After the students have drawn their circuit, get them to help you
draw it on the blackboard for discussion. Go over this circuit and
make sure they see that it is like a circle.
 What happens if one of the wires is disconnected? (The circuit is
opened and the bulb no longer lights. This is called an open
circuit.)
 Have them help you trace the path of electrons in the closed
circuit.
4. (5 minutes)
 Move on to what is happening inside the wires. How are the
electrons moving?
 Ask students to draw on the worksheet how electrons would be
moving with respect to the atoms inside the wire. (The atoms
would be stationary and the electrons would be moving down the
wire in one direction or the other.)
 Now consider that the circuit was opened somehow. Draw the
electrons in the wire now . (Electrons would be moving around
each atom, but would not travel down the wire.)
5. (10 minutes)
 Introduce the ideas of conductors and insulators. (In a
conductor, electrons are free to move. In a completed circuit,
electrons can move around just like in the wire in #4 of the
worksheet. Current can flow in a conductor. In an insulator,
electrons are tightly bound to the nucleus of each atom. They
cannot leave their atoms to flow as a current. Even in a
completed circuit, the electrons in an insulator will behave like
those in the wire in #5 of the worksheet. Current does not flow in
an insulator.)
 Ask the students to sort the materials from their bags into two
piles, one for conductors and one for insulators.
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Electricity and Magnetism, Part 1
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Have students fill out the chart (#6) in the worksheet with their
predictions as they go.
6. (5 minutes)
 After giving students some time to sort the test materials, ask
them to brainstorm about how to test for conductivity in their
materials.
 Steer the discussion towards the method using the battery, two
test leads (insulated wires with alligator clips at each end), and a
test object inserted between the leads. If some students have
another equally good idea of how to do this, allow them to use
their own method.
 Have students sketch their test circuit in the worksheet.
 Then have students test the materials to see if they properly
sorted them.
7. (5 minutes)
 Go over the results of the conductivity test and ask students to
draw any conclusions (e.g., metal objects conduct electricity).
 Ask the students to propose uses for the two classes of
materials. (e.g.: Wires in an electrical cord would be made from
a conducting material; electrical cords have an insulating
material around them so we don’t get shocked.)
8. (5 minutes)
 Hand out the bag of special materials.
 Have students guess whether each item will conduct electricity
or not. Have students test the materials. They will need some
guidance, especially for the diode and LED.
 Ask students which materials surprised them and why.
 Explain what each item is and that it has special properties that
make it behave differently than other similar materials. (The
diode and LED (light emitting diode) conduct electricity in only
one direction. The LED also gives off light of a specific color
when it is in the conducting mode. The ITO coated glass
conducts electricity because it has a transparent electrode on
one side. The conductive polymer conducts electricity because
of its special chemical structure.)
Part 1B: Static Electricity
Objectives:
After participating in the program Electricity and Magnetism, Part 1B,
students will be able to:
 relate static electricity to the parts of the atom
 express the difference between static electricity and electric
current
 explain that electrons may be removed from an atom and
transferred to another object, leaving that object charged
 describe how a discharge or spark is created when electrons
jump from one object to another to re-establish charge neutrality
 recognize that like charges repel
 recognize that opposite charges attract
 name several types of static electricity
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Electricity and Magnetism, Part 1
Vocabulary:
electroscope - an instrument for detecting very small charges of
electricity
static electricity - stationary electrical charges, as those resulting
from friction
Lesson Plan:
Materials:
For each group:
 aluminum foil – one 6” x 6” piece
 aluminum foil – two ½” x 3 ½ “ strips (length may vary
depending on cup size)
 clear plastic cup (or other plastic cups with a view window
cut)
 small paper clip
 tape
For each student:
 balloon
 piece of wool cloth (approximately 12” x 12”)
 string
 worksheet
Teacher/Volunteer Preparation:
1. Electroscope construction preparation: Cut the aluminum foil pieces
(two ½ “ x 3 ½” strips and one 6” x 6” piece per group). The length of the
strips may vary depending on the cups used. When hung on the paper
clip, the two strips should not touch the table. To make it easier for
students to insert the paper clips, pre-punch holes in the bottoms of the
plastic cups. A large safety pin tip will work well here. If the cups are
translucent, cut out a “window” in one side of the cup so that the hanging
strips may be clearly seen. Leave enough of the cup so that it can
support itself on a table top.
Time:
activity 1:
activity 2:
activity 3:
activity 4:
activity 5:
10 minutes
10 minutes
5 minutes
5 minutes
10 minutes
Activities:
1. (10 minutes)
 Each group should make an electroscope1,13 to demonstrate that
like charges repel.
 Refer to Figure E&M_1_1 as the electroscope is constructed.
 Fold out the inner loop of the paper clip and straighten it.
 Hang the two aluminum foil strips (½ “ x 3 ½”) on the hook still
left in the paper clip.
 Push the straightened end of the paper clip through the hole
from inside the cup.
 When the cup is placed on a table bottom-side up, the two strips
should hang beneath the cup without touching the table. Make
sure the strips hang straight and are fairly close to one another.
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Electricity and Magnetism, Part 1
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Secure the paper clip to the cup with tape. This works best
when taping on the outside of the cup where the straight part of
the paper clip comes through.
Wad up the square piece of aluminum foil in a ball and press it
onto the top of the paper clip. Do not wad the foil up too tightly
before pressing it onto the paper clip.
Students have now built an electroscope. Put this aside for a
later experiment.
2. (10 minutes)
 Give a balloon to each student and ask them to blow it up.
 Have the students rub a piece of wool on the balloon several
times and try to stick it to the wall or their shirt, etc. Let them
play with this a bit to see what else the charged balloon will do.
 After a few minutes, ask the students to stop and describe what
they experienced. (Students should report things such as being
able to stick the balloon to something, making their hair stand up,
hearing sparks, etc.)
 Does anyone know what causes these things to happen? (static
electricity)
 Ask the students to think of other examples of static electricity.
(walking across a carpet and touching a metal object, getting out
of a car that has cloth seats, pulling two socks apart right out of
the dryer, lightning, spark plugs, etc.)
3. (5 minutes)
 Now give each student a string and ask them to tie it to their
balloon.
 Work in pairs for this. Have the two students in each pair charge
their balloon and hold it by the end of the string.
 By holding the balloons by the strings, ask students to try to
bring the two balloons together (you can also tape the two
strings together in a doorway with the two balloons hanging at
the same level).
 What do students observe? (Students should report that the two
balloons do not want to be near each other; that the two balloons
push each other away  repel each other.)
 What is happening? Can anyone explain what happened to the
balloon when you rubbed it with the wool cloth? (When the
balloon was rubbed with the wool cloth, electrons were removed
from the wool by friction and were transferred to the balloon.)
 What charge does the balloon now carry? (The electrons cannot
easily get off the balloon, so the balloon is charged negatively.)
 How does this help the balloon to stick to the wall? (An
uncharged object attracts a charged object. When the negatively
charged balloon comes close the wall, the part of the wall
nearest to the balloon becomes positively charged – electrons in
the wall just move over a bit. Then the negative balloon can
stick to the positive part of the wall. Oppositely charged objects
are attracted to each other.)
 Why did the two negatively charged balloons push each other
away? (Two negatively charged balloons repel each other.
Similarly charged objects repel each other.)
4. (5 minutes)
Page 7
Electricity and Magnetism, Part 1
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Charge up the balloon and bring it near the aluminum foil ball of
the electroscope13. As the balloon approaches the ball, the two
leaves hanging below should start to move apart. If the ball is
touched, the strips will jump apart.
Observe the strips as the balloon is moved towards and away
from the ball. (As long as the balloon still retains some charge,
the strips should come back towards one another when the
balloon is moved away. Sometimes the strips will be
permanently deformed by the moving apart so that the
electroscope will not work again until the strips are
restraightened and made to hang close together. Also, if the
balloon touches the electroscope, some charge will be
transferred. In that case, when the balloon is moved away, the
strips will stay far apart. You can briefly touch the Al ball with
your finger to remove excess charge from the electroscope and
the strips will fall back together.)
What happened? (As the negatively charged balloon is brought
near the electroscope, electrons in the ball will travel down the
paper clip and crowd onto the foil leaves. The Al strips now have
a net negative charge. They will repel each other and move
apart. As the balloon is moved away, the electrons flow back to
the ball from the strips and the neutral foil leaves can now come
back to their original position. If the balloon touches the ball of
the electroscope, electrons will jump suddenly from the balloon
onto the electroscope. The resulting negative charge on the foil
leaves will cause them to jump apart as well. A net negative
charge can be left on the electroscope. As mentioned above,
the extra electrons may be removed by touching the ball with
your finger.)
5. (10 minutes)
 Go over things learned. (Objects can be charged by friction.
When this happens, electrons are removed from one object and
are collected on another object (protons do not move). Similarly
charged objects repel each other; oppositely charged objects
attract one another. When a charged object is brought near a
neutral object or an oppositely charged object, electrons can
jump from the neutral object to the positive object, or from the
negative object to the neutral object, or from the negative object
to the positive object in order to equalize the charges. This
movement of charge takes place instantaneously and is called
static electricity. Static electricity discharges can do work
(lighting up neon glow tube, setting a tree on fire during lightning
strike, etc.).)
References and Extension Ideas:
The following resources were used in developing this lesson plan. Some of the activities
were adapted from these sources. Many ideas for extension activities can be found in
them as well.
1. The Thomas Edison Book of Easy and Incredible Experiments,
Thomas Alva Edison Foundation, John Wiley & Sons, Inc., New
York, 1988.
2. www.beakman.com
3. Foss Magnetism and Electricity Module
Page 8
Electricity and Magnetism, Part 1
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
www.freeweb.pdq.net/headstrong/mag.htm
www.freeweb.pdq.net/headstrong/mag2.htm
www.pausd.palo-alto.ca.us/k6science/electric/e_tips.html
www.edtech.kennesaw.edu/web/electric.html
Exploratorium Science Snackbook or
www.exploratorium.edu/snacks/
www.pbs.org/ktca/newtons/12/electric.html
www.pbs.org/wgbh/nova/teachersguide/lightning/lightning_sp1.html
www.pbs.org/wgbh/nova/specialfx/fxguide/fxmshtr2.html
www.pbs.org/saf/4_class/45_pguides/pguide_605/4565_image.html
www.pgs.org/saf/4_class/45_pguides/pguide_604/4564_shark.html
www.pgs.org/saf/4_class/45_pguides/pguide_602/4542_storm.html
www.chss.montclair.edu/~pererat/pertel.html
www.chss.montclair.edu/~peretat/perbuild.html
www.chss.montclair.edu/~pererat/perwirls.html
The Science Teacher, October 1999, “Electromagnetic/Mechanical
Resonator”, pp. 56-58.
Page 9
Electricity and Magnetism, Part 1
E&M_1_1. Illustration of electroscope construction.
a) Fold out inner loop of paper clip:
b) Hang aluminum foil strips on hook: c) Push paper clip through hole in cup:
d) Tape paper clip in place:
e) Press aluminum foil onto top of paper clip
(optional view window shown):
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