What are the strengths of electromagnets

Contributed by:

kevin Mon, Jan 17, 2022 08:55 PM UTC

Electric current flowing through a wire wound around an iron nail creates a magnetic field, which caused an iron
nail to become a temporary magnet. The nail can then be used to pick up paper clips. When the electric current is cut off, the nail loses its magnetic property and the paper clips fall off.

1. MACHINES
Strength of Electromagnets
Purpose Materials
To test the strength of an electromagnet q Data Sheets 1 and 2
(one set per student)
by changing its parts q 2 non-galvanized steel
nails, 10 cm (4 in.)
Process Skills q 1 length of insulated
Observe, measure, form a hypothesis, collect 20-gauge wire, 30 cm
(1 ft.) long with the
data, interpret data, identify and control insulation trimmed
off the ends
variables, communicate, draw conclusions q 1 length of insulated
20-gauge wire, 60 cm
Background (2 ft.) long with the
Magnetism is a force that can push or pull objects insulation trimmed
off the ends
made of some kinds of metal. It is caused by the q 2 new D cell batteries
invisible magnetic field that surrounds a magnet. q 30 folded (used) staples
q electrical tape
The magnetic field is made up of lines of force.
The lines of force flow through and around the magnet. When the right
kind of metal is inside the magnetic field, the magnet attracts it.
Permanent magnets always have a magnetic
field. Magnets on your refrigerator are this
kind of magnet. Temporary magnets are + -
not magnetic all the time. An electromagnet
is a kind of temporary magnet.
It can be turned on or off. When
it is connected to an electric current,
an electromagnet has a magnetic field.
Then it can push or pull some metal
objects. It can be turned off by
disconnecting it from the electricity.
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2. EXPERIMENT Machines—Strength of Electromagnets
In this experiment, you will make
an electromagnet. Then you will exposed wire
steel nail
test how changing two variables insulated wire
can affect its strength.
Safety: Electromagnets can get Figure A
hot very quickly. Be careful when
2. Repeat step 1, but now wrap
touching them! Use cloth gloves
the 60 centimeter (2 ft.) piece
if available. Remove wires from
of wire around the other nail
batteries at all times when you
in 20 coils. Once again, leave
are not using them.
some loose wire at each end
Time – About 1 hour of the nail.
Grouping – Small groups
Hypothesis: In this activity, you
and individuals
will find out how many staples
different electromagnets can pick
up. You will change two variables
Making the Electromagnets
to make different electromagnets:
1. Wrap the 30-centimeter (1 ft.)
the number of wire coils around
piece of wire around one of
the nail (10 or 20) and the number
the nails 10 times. Wrap the
of D cell batteries (1 or 2). With
wire tightly and neatly into
your group, discuss what you think
a coil (see Figure A). Make
will happen. For each variable,
sure that it is coiled in a single
predict which electromagnet will
direction. Be sure the coils do
pick up more staples and why.
not overlap. Leave some loose
Then complete the hypotheses on
wire at each end of the nail.
your own copy of Data Sheet 1.
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3. EXPERIMENT Machines—Strength of Electromagnets
Test 1: Electromagnets with One Battery [Note: Immediately after removing
1. Pile 30 folded staples on a flat the staples, disconnect one end
surface in your work area. of the wire from the battery.
2. Pick up the nail that has 10 The longer you leave it connected,
wire coils. Tape one end of the the hotter the wire will become!]
exposed wire to each end of 1 Count the number of staples your
D cell battery (see Figure B). electromagnet picked up. Record
The tape must be strong enough this number in the first table on
to hold the nail in midair. Your Data Sheet 2 in the appropriate
nail is now an electromagnet! row under Trial 1.
Remember to be safe when 4. Repeat this test two more times
touching it. with the same electromagnet.
Record the results under Trial 2
D cell battery
and Trial 3 for this type of
tape
electromagnet.
+ - 5. Add together the number of
steel nail exposed wire staples the electromagnet picked
up in Trials 1, 2, and 3. Divide
insulated wire Figure B
the total by 3. Record this
number as the Average in the
3. Hold onto the battery, letting correct row of the data table.
the coiled nail hang below it.
6. Repeat steps 1–5 using the nail
Slowly move the nail around in
with 20 coils. [Note: Remember
the pile of staples for 5 seconds
to disconnect one end of the
and then raise it above the pile.
wire from the battery as soon
In a nearby area, remove the
as you have removed the staples
staples from your electromagnet.
each time.]
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4. EXPERIMENT Machines—Strength of Electromagnets
Test 2: Electromagnets with D cell battery tape
Two Batteries
1. N
ow you will repeat the entire
exploration, but you will use + - + -
exposed wire
2 D cell batteries. Pick up the
nail that has 10 wire coils. Tape
one end of the exposed wire Figure C
steel nail insulated wire
to one of the battery’s positive
ends (the end with the + sign). 2. Repeat step 1, but this time use
Tape the other end of the the 2 connected batteries as you
exposed wire to the second test the nail that has 20 wire
battery’s negative end (the coils. Complete three trials
end with the – sign). Hold with this electromagnet and
onto both batteries so the record the data in the second
first battery’s negative end table on Data Sheet 2.
touches the second battery’s
positive end (see Figure C).
You now have a new type
of electromagnet. Repeat the
tests from Part 1 using this
electromagnet. Complete three
trials and record the data in the
second table on Data Sheet 2.
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5. EXPERIMENT Machines—Strength of Electromagnets Data Sheet 1
Name _____________________________________________ Date _______________
Hypotheses: Think about the variables used in this activity (10 or 20
wire coils and 1 or 2 batteries). Then complete each hypothesis.
1. W
ill the electromagnet with 10 wire coils or 20 wire coils pick up
more staples? Why do you think this will be so?
2. W
ill the electromagnet with 1 or 2 batteries pick up more staples?
Why do you think this will be so?
3. W
hich combination of wire coils and batteries will pick up the most
staples? Why do you think this will be so?
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6. EXPERIMENT Machines—Strength of Electromagnets Data Sheet 2
Name _____________________________________________ Date _______________
Collect Data
Test 1: Number of staples picked up when connected to one battery
Electromagnet
Trial 1 Trial 2 Trial 3 Average
Description
nails with
10 coils
nails with
20 coils
Test 2: Number of staples picked up when connected to two batteries
Electromagnet
Trial 1 Trial 2 Trial 3 Average
Description
nails with
10 coils
nails with
20 coils
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7. EXPERIMENT Machines—Strength of Electromagnets Questions
Name _____________________________________________ Date _______________
Analyze Data
1. Did your data for each variable support or not support your hypotheses?
Why do you think this was so?
2. W
hen you found the average of your results, which combination
of variables made your electromagnet pick up the most staples?
3. When you found the average of your results, which combination
of variables made your electromagnet pick up the fewest staples?
4. W
hich variable affected the results more—number of coils or number
of batteries? Why do you think this variable was so important?
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8. EXPERIMENT Machines—Strength of Electromagnets Questions
Name _____________________________________________ Date _______________
5. W
hy was it important to conduct three trials with each electromagnet
and find the average results?
Draw Conclusions
1. Would the electromagnets have worked if you had used a piece
of wood or plastic instead of a nail? Why or why not?
2. How did the electric current from the battery cause the nail to act
as a magnet?
3. W
hy did the safety tips suggest disconnecting just one wire from
the battery instead of both wires?
4. H
ow would you make an electromagnet that was stronger than any
of the ones you used in this activity?
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9. MACHINES
Strength of Electromagnets
TEACHING TIPS
This Process Activity will help students understand the properties of electricity and
magnetism, and the relationship between these two forces. An electric current can
cause certain metal objects to develop a magnetic field that can affect other metal
objects. By exploring variables, students come to understand the features that affect
the strength of electromagnets. When using electromagnetism, safety is extremely
important.
SET-UP and n Before the experiment, strip the insulation off the ends of the wires. Use
PROCEDURES wire cutters to carefully pull about 1 centimeter (0.5 in.) of insulation
from each end to create leads of exposed wire.
n Before students test the electromagnets, you may want to conduct your
own investigation so you will be able to judge whether students’ results
are accurate, given the available materials.
n Discuss the importance of wrapping the wire around the nails neatly and
in the same direction. If students change the direction of their wrapping
partway through, the electrons will not all align in the same direction.
This will decrease the strength of the electromagnet. It doesn’t matter
which end of the wire is connected to the battery in terms of magnetic
strength. View the wire as neutral. What will vary is the polarity (north
versus south pole) of the electromagnet and the flow of electric current.
n To avoid distraction and maximize lab safety, pass out materials only after
students have finished reading through their instructions and making
their hypotheses.
n If using cooperative groups, assign jobs for each student within each
group. Examples include getter, recorder, wire wrapper, staple counter,
materials manager, and reporter.
n einforce relevant vocabulary terms (e.g., electromagnet, magnetic field,
R
electric current) throughout the experiment.
SAFETY n iscuss all safety rules prior to allowing students to begin the experiment.
D
Emphasize the importance of disconnecting the wires from the batteries
immediately after the collection of data and the use of cloth gloves because
of the potential for heat in the electromagnets.
MATERIALS n he best wire to use for this experiment is magnet wire, which is available
T
in electronics and hardware shops. Other types of wire, including
standard electrical wire and telephone wire, will also work.
n
Test the nails to be sure they become magnetized when assembled as part
of an electromagnet. Most iron or steel nails should work well.
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10. EXPERIMENT Machines—Strength of Electromagnets
n Have extra materials available in case of dead/weak batteries, overly
stripped wire, or other material faults. Other small batteries, such as
AAA, AA, C, and 9-volt, may be used if D cell batteries are not available.
n Different sizes of batteries, different lengths of wire, and different sizes
of nails can all be substituted in this experiment. Results will vary, and
student data sheets will need to be adjusted accordingly. Remember that
if stronger batteries are used, the wires will heat up faster.
EXTENSIONS and n ariation/Inquiry Science: Repeat the experiment, but this time provide each
V
VARIATIONS group with different sizes of batteries, such as AAA, AA, C, and 9-volt.
How do different sizes of batteries affect the results? SAFETY NOTE:
Do not use stronger batteries, as these may be dangerous to handle once
hooked up to wires.
n Research/Technology: Have students use Science A–Z resources and other
materials to research how magnets work and the many uses of magnets,
including electromagnets. Ask students to compile and present their
research in a digital slideshow to share with other classes.
n ESL/ELL: Have students create a dictionary or word wall in which key
content vocabulary words are alphabetized, defined, and illustrated,
such as experiment, hypothesis, observation, data, results, and conclusion.
Also include vocabulary relevant to the lesson, such as magnetism, force,
metal, magnetic field, permanent, temporary, electromagnet, and electric current.
For more vocabulary resources, visit .
n Home Connection/Technology: Have students search and list everything in
their house that uses magnets. Compile all students’ lists into a class list.
Then students can find or create an image of each magnetic item to
contribute to a class bulletin board or mural about magnets.
n Field Trip: Visit a power plant or recycling center. Ask a technician to
explain the roles that magnets play.
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11. EXPERIMENT Machines—Strength of Electromagnets Data Sheet 1
ANSWER KEY
EXPERIMENT Machines—Strength of Electromagnets Data Sheet 1
Name _____________________________________________ Date _______________
Hypotheses: Think about the variables used in this activity (10 or 20
wire coils and 1 or 2 batteries). Then complete each hypothesis.
1. W
ill the electromagnet with 10 wire coils or 20 wire coils pick up
more staples? Why do you think this will be so?
Hypotheses will vary and should be supported by logical reasoning.
2. W
ill the electromagnet with 1 or 2 batteries pick up more staples?
Why do you think this will be so?
Hypotheses will vary and should be supported by logical reasoning.
3. W
hich combination of wire coils and batteries will pick up the most
staples? Why do you think this will be so?
Hypotheses will vary and should be supported by logical reasoning.
© Learning A–Z All rights reserved. 5 www.sciencea-z.com
© Learning A–Z All rights reserved. 3 www.sciencea-z.com

12. EXPERIMENT Machines—Strength of Electromagnets Data Sheet 2
ANSWER KEY
EXPERIMENT Machines—Strength of Electromagnets Data Sheet 2
Name _____________________________________________ Date _______________
Collect Data
Test 1: Number of staples picked up when connected to one battery
Electromagnet
Trial 1 Trial 2 Trial 3 Average
Description
Results will vary depending on the materials used. Each response
nails with
should
10 coils The number of staples listed under each trial may
accurately
vary within each row but will likely be similar. In
calculate the
Test 1 (1 battery), the nail with 20 coils will likely
nails with average of
pick up the greater number of staples.
Trials 1, 2, and
20 coils
Test 2: Number of staples picked up when connected to two batteries
Electromagnet
Trial 1 Trial 2 Trial 3 Average
Description
Results will vary depending on the materials used Each response
nails with and how well the batteries are connected. should
10 coils accurately
The number of staples listed under each trial may
calculate the
vary within each row but will likely be similar.
average of
In Test 2 (2 batteries), the nail with 20 coils will
Trials 1, 2, and
nails with again likely pick up the greater number of staples
3 on both rows.
20 coils because more coils will allow more current to flow
and should yield a stronger electromagnet.
© Learning A–Z All rights reserved. 6 www.sciencea-z.com
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13. EXPERIMENT Machines—Strength of Electromagnets Questions
ANSWER KEY AND EXPLANATIONS
Analyze Data
1. Did your data for each variable support or not support your hypotheses? Why do you think
this was so?
Results will vary but should accurately reflect an analysis of the recorded data and a comparison
of that data against the previously recorded hypotheses.
2. When you found the average of your results, which combination of variables made your
electromagnet pick up the most staples?
Results will vary but should accurately reflect an analysis of the recorded data. Students are likely
to indicate that the electromagnet with 20 coils and 2 batteries picked up the most staples.
3. When you found the average of your results, which combination of variables made your
electromagnet pick up the fewest staples?
Results will vary but should accurately reflect an analysis of the recorded data. Students are likely
to indicate that the electromagnet with 10 coils and 1 battery picked up the fewest staples.
4. Which variable affected the results more—number of coils or number of batteries? Why do
you think this variable was so important?
Results will vary but should accurately reflect an analysis of the recorded data. The number of coils
is likely to affect the results more than the number of batteries. When more coils are added around
the core of the electromagnet, more atoms in the nail become polarized, resulting in a stronger magnet.
Students might find that the number of batteries had the greater impact on the results, but the flow
of current from one battery to the next can be affected by how well students held the batteries together
during Test 2.
5. Why was it important to conduct three trials with each electromagnet and find the average
results?
Ideally, at least three trials should be conducted in a science investigation to ensure that results
are reliable. More trials reduce the chances of drawing conclusions based on quirks and errors,
and increase the potential accuracy of measurement.
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14. EXPERIMENT Machines—Strength of Electromagnets Questions
ANSWER KEY AND EXPLANATIONS
Draw Conclusions
1. Would the electromagnets have worked if you had used a piece of wood or plastic instead
of a nail? Why or why not?
The electromagnets would not have worked. A piece of metal—such as iron, cobalt, or nickel—must be
connected to the circuit to allow electric current to create a magnetic field around the core material.
2. How did the electric current from the battery cause the nail to act as a magnet?
The electric current from the battery caused the nail to have a magnetic field around it. This magnetic
field made the nail act as a magnet (an effect). It became an electromagnet. When the battery was
disconnected, the magnetic field went away, and the nail no longer acted as a magnet.
3. Why did the safety tips suggest disconnecting just one wire from the battery instead of both
wires?
The electromagnet has a current running through it only when both wires are connected. Disconnecting
just one wire breaks the circuit and stops the flow of electricity, so disconnecting both wires is not
necessary.
4. How would you build an electromagnet that was stronger than any of the ones you used
in this activity?
Answers will vary but may include the following: use higher-voltage batteries, use more batteries,
wrap the coil around the nail more times, use a longer nail, use a thicker nail, or use a thinner nail.
(These responses may be a good starting point for further inquiry into building electromagnets.
However, always monitor the introduction of new variables for safety!)
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15. MACHINES
Machines with Magnets
Have you ever played with strong
magnets? It’s not always easy to pull Most large magnets are
them apart. But how strong can electromagnets. These
magnets run on electricity,
magnets be?
so people can turn them
This big magnet hangs from on and off.
a crane. A magnetic field around
the magnet attracts certain kinds This big magnet is an MRI
of metal. The magnet is strong machine. Doctors use this machine
enough to lift huge objects such to see inside the body. The magnet
as cars. It can also separate is incredibly strong, so patients
iron from other metals must not bring any metal with
and materials. Once these them. Any nearby metal in the
items are separated, they room would fly into the magnet.
can be recycled. Even a metal button would be
dangerous.
This train can travel over
480 kilometers (300 mi.) per hour,
and it does this without wheels! Magnets
on the track repel magnets under the
train. The magnets are so strong that the
train floats above the tracks. Trains with
wheels move slower because the wheels
rub against the rails and create friction.
MRI machine
oH
ow do magnets make metal move?
oH
ow do people use very strong
magnets?
oW
hat would you do with a very
strong magnet?
Maglev trains are some of the fastest trains in the world.
Credits: top: © Dan Van Den Broeke/Dreamstime.com; center: © iStockphoto.com/Mark Kostich;
center inset: © iStockphoto.com/Luis Carlos Torres; bottom: © Maomaotou/Dreamstime.com
© Learning A–Z All rights reserved. www.sciencea-z.com

16. MACHINES
Machines with Magnets
Have you ever played with strong
magnets? They are hard to pull apart.
Most large magnets are electromagnets.
But how strong can magnets be? These magnets run on electricity. People
can turn them on and off.
This big magnet hangs from
a crane. A magnetic field around
the magnet pulls, or attracts, This big magnet is an MRI
metal to it. The magnet is strong machine. An MRI image
enough to lift huge objects such helps doctors see inside the
as cars. It can also separate body. The magnet is super
iron from other metals. strong. Any nearby metal
Then the metals can would fly into the magnet.
be recycled. Even a metal button would
be dangerous.
This is one of the fastest trains
in the world. It is magnetic. Magnets
on the track push away, or repel,
magnets under the train. The
magnets are so strong that the
train floats.
MRI machine
oH
ow do magnets make metal move?
oH
ow do people use very strong
magnets?
Magnetic trains can go over 480 kilometers (300 mi.) oW
hat would you do with a very
per hour! Trains with wheels are slower. That’s because
strong magnet?
the wheels rub against the rails and cause friction.
Credits: top: © Dan Van Den Broeke/Dreamstime.com; center: © iStockphoto.com/Mark Kostich;
center inset: © iStockphoto.com/Luis Carlos Torres; bottom: © Maomaotou/Dreamstime.com
© Learning A–Z All rights reserved. www.sciencea-z.com

17. MACHINES
Machines with Magnets
Have you ever played with
strong magnets? They are
Most large magnets use electricity.
hard to pull apart. But People can turn them on and off.
how strong can they be?
This big magnet is an
This big magnet hangs
MRI machine. An MRI
on a crane. It is strong
image helps doctors see
enough to lift huge
inside the body. The magnet
objects. It can also
is very strong. Any nearby
separate iron from
metal would fly into the
other metals. Then these
magnet. Even a metal button
metals can be recycled.
would be dangerous.
This is one of the fastest trains
in the world. Magnets on the
track push away, or repel, magnets
under the train. They are so
strong that the train floats!
MRI machine
oH
ow do people use very
strong magnets?
oW
hat would you do with
Magnetic trains can go over 480 kilometers (300 mi.)
a very strong magnet?
per hour! They use magnets instead of wheels.
Credits: top: © Dan Van Den Broeke/Dreamstime.com; center: © iStockphoto.com/Mark Kostich;
center inset: © iStockphoto.com/Luis Carlos Torres; bottom: © Maomaotou/Dreamstime.com
© Learning A–Z All rights reserved. www.sciencea-z.com

18. Magnetism and Electricity
Lesson 4
Name Date
Part 1: Build an Electromagnet
Circle the items that you could use to make an electromagnet. Then draw a diagram
of an electromagnet made with those parts. Label each part on your diagram.
pencil wire eraser tape
penny nail battery string
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19. Storyline Assessment Magnetism and Electricity
Lesson 4
Name Date
Part 2: Answer Questions
Use your electromagnet diagram from Part 1 to answer the questions.
1. L
ist each part you included in your electromagnet and write why you
included it.
2. Is the electromagnet you designed an example of a system?
Why or why not?
3. What causes a magnetic field to form around an electromagnet,
and what effect does it have on nearby metal objects?
Cause:
Effect:
4. What would happen to an electromagnet if the wire were not connected
to the battery at one end?
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20. Storyline Assessment Magnetism and Electricity
Lesson 4
Name Date
Part 3: Ask Questions
There are many ways you can change an electromagnet. Three of these variables
are listed below. For each variable, write a question about an electromagnet that
you could test.
1. number of wire coils
Question:
2. number of batteries
Question:
3. size (voltage) of the battery
Question:
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21. Storyline Assessment Magnetism and Electricity
Lesson 4
ANSWER KEY AND TEACHING TIPS
Connections to the Next Generation Science Standards*
Target Science and Engineering Practice: Asking Questions and Defining Problems
• Ask questions that can be investigated based on patterns such as cause and effect relationships.
Associated Performance Expectation: 3-PS2-3. Ask questions to determine cause and effect
relationships of electric or magnetic interactions between two objects not in contact with each other.
All questions in this assessment relate to the Disciplinary Core Ideas DCI of this Performance
Expectation. Look for the SEP and CCC symbols for questions that specifically address Science
and Engineering Practices and Crosscutting Concepts.
Students identify the components needed to construct an electromagnet and use them to make
a labeled-parts diagram. They answer cause-and-effect questions about electromagnets and write
their own questions that can be investigated and answered through the collection of data.
Part 1: Build an Electromagnet
pencil wire eraser tape
penny nail battery string
Students’ drawings will vary but should include wire, a nail, and a battery, and may also include tape
to attach the ends of the wire to the battery. Each item should be appropriately labeled. Students
may customize their model by adding fewer or more wire loops around the nail or by including more
than one battery. See example.
battery
tape
+ -
nail
wire
* Next Generation Science Standards is a registered trademark of Achieve. Neither Achieve nor the lead states and partners that developed the Next Generation Science Standards was involved in the
production of, and does not endorse, this product.
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22. Storyline Assessment Magnetism and Electricity
Lesson 4
Part 2: Answer Questions
1. nswers will vary, but student responses should reflect an understanding of a system as a set
A
of interacting components. Students should list each of the components they included in their
electromagnet model and the purpose of each. For example:
I included a battery in my model as a source of electricity. I used wire to carry the electricity from
one end of the battery to the other. The wire was wrapped around a nail, which becomes magnetic
when electricity is flowing through the wire. I also used tape to attach the wire to each end of the
battery.
2. M
y electromagnet is a system because it has several parts that work together. All of the parts
are needed for the electromagnet to work.
3. Cause: Electricity from a battery causes a magnetic field to form around the electromagnet.
Effect: The magnetic field can affect nearby metal objects by attracting them, or drawing them
toward the electromagnet.
4. E
lectricity would not flow through the wire. The magnetic field would not form around the nail, and
the electromagnet would not be able to pick up anything. (Note: Electromagnets are turned on and
off by controlling the flow of electricity.)
SEP Part 3: Ask Questions
Questions will vary, but students should ask a question for each variable that can be answered through
the collection of data. Students may list staples, paper clips, or other small metal objects as the items
that will be used in a test to measure the electromagnet’s strength. Examples are provided.
1. n
umber of wire coils
Question: How will the number of wire coils around the nail affect the number of paper clips the
electromagnet can pick up?
Or
If I add more wire coils around the nail, will it make the electromagnet stronger?
2. n
umber of batteries
Question: How will the number of batteries I include in the electromagnet affect the number
of paper clips the electromagnet can pick up?
Or
If I use two batteries instead of one, will the magnetic field around my electromagnet be stronger?
3. s ize (voltage) of the battery
Question: How will the battery’s voltage affect the number of paper clips my electromagnet
can pick up?
Or
If I use a battery with a higher voltage, will my electromagnet be stronger or weaker?
© Learning A–Z All rights reserved. 5 www.sciencea-z.com

23. Storyline Assessment Magnetism and Electricity
Lesson 4
Teaching Tips
If students have trouble performing the tasks on this assessment, ask them to review the data they
collected during the Strength of Electromagnets Process Activity and the electromagnet diagram they
created during Lesson 4. Explain that electromagnets need a battery or other source of electricity as
well as components that can conduct electricity. Both variables tested during the experiment—number
of wire coils around the nail and number of batteries—affected the strength of the electromagnet as
measured by the number of staples the device could pick up. Adding more wire coils around the nail
or an additional battery increases the strength and size of the magnetic field. Point out that metal
objects, such as paper clips and staples, within the magnetic field are attracted to the electromagnet
and move toward it. The magnetic field around an electromagnet can be turned on and off by controlling
the flow of electricity. Finally, remind students that good scientific questions are based on observations
and can be answered through the collection of data. Well-thought-out investigations can reveal patterns
or cause-and-effect relationships.
For students who complete their work early or are ready for an extra challenge, assign additional
resources related to this topic found on the Grade 3 Forces and Interactions NGSS page on Science A–Z.
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