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Teacher’s Notes - Electricity and Magnetism, Part 1
Electricity and Magnetism, Part 1
Supplemental and Background Information
For Teachers and Volunteers
Rationale:
According to the new California Science Standards, electricity and
magnetism are important science concepts for 4th grade students. While
the new science standards have not yet been implemented in most
schools, these modules were designed to complement these standards.
Specific science standards addressed in this Electricity and Magnetism
lesson plan are:
3rd grade:
 Matter is made of small particles called atoms that are too small
to see with the naked eye.
 Energy can be carried from one place to another by an electric
current.
 Students are asked to predict the outcome of a simple
investigation and compare the result with the prediction.
 Students are asked to collect data in an investigation and
analyze the data to develop a logical conclusion.
4th grade:
 Students can design and build simple series and parallel circuits
by using wires, batteries, and bulbs.
 Electrically charged objects attract or repel each other.
 Electrical energy can be converted to light (also heat and
motion).
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
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
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Teacher’s Notes - Electricity and Magnetism, Part 1
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 Notes:
1. Worksheet item 1 asks students to think of practical application of
electricity that they have come in contact with.
2. Understanding the main parts of an atom (electron, proton, and
neutron) allows students to understand electricity on the molecular level.
If they have not yet studied the atom, worksheet item 2 and any
explanations dependent on this knowledge may be skipped. Students
will still gain practical knowledge about electricity and electrical
properties of materials by doing the activities.
3. Since there are several ways to make the light bulb circuit, the
students will be asked to use two wires, the battery, and a bulb in its
holder. After drawing their circuit in worksheet item 3, it will be
discussed. The main point for the students to understand is 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.)
The current path (or path of the electrons) can be traced in the closed
circuit.
4. How are the electrons moving inside the wires? On worksheet item 4,
the electrons should be drawn with respect to the atoms inside the wire.
(The atoms would be stationary and the electrons would be moving in
one direction or the other. The atoms are depicted as small open circles
on the worksheet. Students need to add the electrons moving around
them.) Worksheet item 5 considers what happens when the circuit is
opened somehow. (Electrons should be shown moving around each
atom, but not traveling down the wire.)
5. 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.
6. Students are asked to sort the materials into two categories,
insulators and conductors. This requires them to use their common
sense knowledge to predict the outcome of an experiment. They are
asked to record in worksheet item 6, the objects along with their
predictions. The are next led through a brainstorming session where
they are asked to help design a conductivity test. The recommended
method uses the battery and two test leads (insulated wires with alligator
clips at each end). Test objects are to be inserted between the two test
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Teacher’s Notes - Electricity and Magnetism, Part 1
leads. If some students have another equally good idea of how to do
this, allow them to use their own method. The test circuit should be
drawn in worksheet item 7. As students perform their conductivity tests,
results are recorded in the chart in worksheet item 6.
7. Test results are discussed with the class and students are asked to
draw conclusions (e.g., metal objects conduct electricity). Students are
asked 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. Some special materials were included in the materials bag. Students
will need guidance for testing the LED (light emitting diode). It is very
important that the LED leads are not shorted during testing (this is
equivalent to touching the two test leads together.) Students should also
pay attention to the battery polarity when testing the LED. (The LED
conducts electricity in only one direction. The LED also gives off light of
a specific color when it is in the conducting mode. The color is due to
the characteristic bandgap of the semiconductor material making up the
LED.)
Answers to the worksheet are located in the file:
E&M_1_wksht_key.
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
4. www.freeweb.pdq.net/headstrong/mag.htm
5. www.freeweb.pdq.net/headstrong/mag2.htm
6. www.pausd.palo-alto.ca.us/k6science/electric/e_tips.html
7. www.edtech.kennesaw.edu/web/electric.html
8. Exploratorium Science Snackbook or
www.exploratorium.edu/snacks/
9. www.pbs.org/ktca/newtons/12/electric.html
10. www.pbs.org/wgbh/nova/teachersguide/lightning/lightning_sp1.html
11. www.pbs.org/wgbh/nova/specialfx/fxguide/fxmshtr2.html
12. www.pbs.org/saf/4_class/45_pguides/pguide_605/4565_image.html
13. www.pgs.org/saf/4_class/45_pguides/pguide_604/4564_shark.html
14. www.pgs.org/saf/4_class/45_pguides/pguide_602/4542_storm.html
15. www.chss.montclair.edu/~pererat/pertel.html
16. www.chss.montclair.edu/~peretat/perbuild.html
17. www.chss.montclair.edu/~pererat/perwirls.html
18. The Science Teacher, October 1999, “Electromagnetic/Mechanical
Resonator”, pp. 56-58.
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