Students will complete several activities that reinforce the concept that all simple machines transfer force.
- Drinking glass or cup
- Index card
- One clay marble
- One small toy car
- Masking tape
- One pencil
- Three books (about 1
- Paper Grid (pdf)
Twirling Helicopter Toy--Screw
For each student:
- IVORY soap
- Plastic knife
- Paper (cut into 4 1/4 x
- Paper towels
All Geared Up--Wheels and Axles (Gears)
- Two plastic milk caps
- One lid that is larger
than a milk cap (e.g., a
yogurt cup lid, cottage
cheese container lid, or
a Cool Whip lid)
- Three strips of
(1/2 x perimeter of
Flag Raiser--Fixed Pulley
- Thread spool
- Pencil or wooden dowel
(small enough to slide
through the hole in the
- String (4 ft. in length)
- Paper for flag (4 1/4 x
- 3rd Grade CORE Academy Resource Book, 2003
- Push and Pull, by Patricia J. Murphy; ISBN 0516268643
- Pushing and Pulling (Science For Fun), by Gary Gibson;
- How Do You Lift A Lion?, by Robert E. Wells; ISBN 0807534218
- The New Way Things Work, by David Macauley (1998);
- Simple Machines, by Deborah Hodge; ISBN 1550743996
- MachinesSpectacular Science Projects, by Janice Van Cleave;
- Physics Lab in the Hardware Store, by Bob Friedhoffer;
- Playground PhysicsSimple Machines, by Bob DeWeese; ISBN 1557993017
- Science Experiments With Simple Machines, by Sally Nanivell-Aston;
- Windows on Science, Primary Vol. 3, Force and Motion,
Lessons 1-3, 5
- Windows on Science, Primary Vol. 3, Work and Machines, Lesson 1
- Science Alliance # 3, Machines
Background for Teachers
Objects at rest will remain at rest unless acted upon by an unbalanced
force. Objects in motion will remain in motion at the same speed and
direction unless acted upon by an unbalanced force. A force is a push or
A simple machine is a device that makes work easier. The six simple
machines are: inclined plane, wedge, screw, lever, wheel and axle, and
pulley. All simple machines transfer force. Some change the direction of
force, while others change the strength of the force. Still others change
both the direction and the strength. Most simple machines make work
easier by allowing you to use less force over a greater distance to move
an object. Some machines make work easier by allowing you to move
things farther and/or faster. In these machines, a larger force is required,
but over a shorter distance.
Intended Learning Outcomes
1. Use Science Process and Thinking Skills
2. Manifest Scientific Attitudes and Interests
3. Understand Science Concepts and Principles
4. Communicate Effectively Using Science Language and Reasoning
Invitation to Learn
Set an index card over the mouth of a glass/cup. Set a penny on
the card directly over the mouth. Have the students predict the
movement/action of the penny if the paper is flicked off the glass/cup.
Flick the card with your finger. Where does the penny go? Why?
(The penny is at rest and wants to remain at rest. The flicking force is
applied to the card, so the card moves and the penny drops into the
- Place one end of the ruler ramp onto one book.
- Place the Paper Grid about two car lengths away from
the bottom end of the ramp.
- Tape a pencil along the edge of the Paper Grid closest to the
- Position the car, with the clay marble sitting on top, at the top of
the raised ramp.
- Have the students predict what will happen to the car and the clay
marble when the car hits the pencil.
- Let go of the car and allow it to roll down the ramp and collide
into the pencil.
- Measure how far the clay marble falls from the car.
- Repeat the procedure using two books, then three books.
- Discuss what happened and why.
(The car stops when it hits the pencil, but the clay marble
continues to move forward until the force of gravity and air
molecules brings it to a stop. Raising the height of the ramp
causes the car to reach a higher speed before it hits the pencil.
Therefore, the clay marble moves at a higher speed and will move
farther before the force of gravity and air molecules brings it to a
- Remind the students that objects will only move when a force is
applied. A force is either a push or a pull.
- The students will write down many, varied, and unusual ways to
move a penny (or a paper clip, etc.) one foot (12 inches).
- The students will categorize their ideas into pushing forces,
pulling forces, or both.
- Pour the rice into the sock. Close the end
with a rubber band or string.
- Attach the spring scale to the rubber band
or string and lift the rice-filled sock
straight up to the height of three books.
- Observe how much force is needed and
record on the Uphill-Inclined Plane worksheet.
- Place one end of the plank of wood on top of five books and the
other end on the table to form a ramp.
- Place the sock (with the spring scale attached) on the bottom part
of the ramp. Pull the sock to the top of the ramp.
- Observe and record how much force is needed.
- Repeat steps 4 6 using three books
- Repeat steps 4 6 using one book.
- Analyze the results and discuss how they relate to F = W x D.
(The ramp is an inclined plane. It is used to move an object to a
higher level with less force than lifting straight up. When using
an inclined plane, you must move the object a greater distance
than if you lifted it straight up, but it takes less force.)
Twirling Helicopter ToyScrew
- Print the Toy Helicopter Pattern on both regular
weight paper and cardstock.
- Give each student one pattern printed on regular weight paper,
one pattern printed on cardstock, one large paper clip, and one
small paper clip.
- Tell the students that they are going to be making helicopters
that require one pattern and one paper clip each. Ask the
students to come up with all the different possible combinations
and write them on the board.
- Have the students predict which combination will produce the
gentlest decent. (Option: Record the number of predictions for
each combination by using tally marks.)
- Instruct the students to cut out the patterns on solid lines A, B and
F and to fold on dotted lines C and D. Then, fold along dotted
- Have each student test each of the possible combinations by
lifting his/her toy helicopter up high and letting go.
- Review student predictions. Were they correct?
- Analyze how the helicopter is
acting as a simple machine. (The
toy helicopter twirls in a spiral as it
drops. The twirling blades act as a
screw that helps you lower (or lift) things with less force. Turning in a
spiral allows the helicopter to drop
with less force. It lands softly
instead of crashing down.)
- Unwrap the bar of soap.
- Trace around the bar of soap onto
- Draw a simple design onto the
paper (no larger than the bar of
- Cut out the design.
- Lay the cut-out design onto the bar of soap and trace around the
- Turn the bar of soap over and lay the design onto the side of the
bar of soap (being careful of the placement) and trace around the
- Place the bar of soap onto a paper towel.
- Carefully carve the design out of the soap by first cutting the soap
into a block, followed by rounding the edges, and finally
carving the details (encouraging the students to try to keep the
shavings on the paper towel).
- The soap can be smoothed by rubbing the surface with a small
amount of water.
- Analyze how the knife was being used as a simple machine to
make work easier. (The knife is a wedge shaped like two inclined
planes back-to-back. The narrow edge of the knife blade enters
and makes a path for the larger part of the knife that follows.
Once an opening is made, the soap is easily pried apart by the
gradually widening body of the knife blade.)
All Geared UpWheels and Axles (Gears)
- Glue the strip of cardboard around
the edge of each lid.
- Trim the cardboard to the correct
- Interlock the two milk cap lid gears
and gently rotate each.
- Analyze the direction that each gear turns.
- Interlock two different sizes of lids. Mark each gear where they
originally touch. Gently rotate each. Count how many times the
small gear rotates for each single rotation of the large gear.
- Analyze how the gears are working like a simple machine.
(Gears are wheels with teeth that turn and work together.
Different sizes and arrangements of gears do different jobs. A
large gear turning a smaller one will give you more speed. A
small gear turning a large one will give you more power.)
Flag RaiserFixed Pulley
- Decorate/color a flag created using the 4 1/4 x 5 1/2 paper.
- Place the pencil/wooden dowel through the hole in the thread
spool, making sure that the spool can turn easily.
- Tie the ends of the string together.
- Tape one side of the flag to the string.
- Place the loop of the string over the spool, with the flag
hanging near the bottom of the loop.
- Have one student hold the ends of the pencil/wooden dowel
high over his/her head.
- Have the other student pull down on the string opposite the
- Observe the distance the string is pulled
and the distance and direction the flag
moves up. Relate this to simple machines.
(The spool is a fixed pulley that allows you
to pull down on the string and raise the flag
upward. Placing a fixed pulley at the top
of a tall flagpole makes the job of raising a
flag easier than if you had to carry the flag
up the pole. A fixed pulley makes work easier by changing the
direction of the force. Pulling down is easier because you can use
the weight of your body and the force of gravity to help you.)
See 3rd Grade CORE Academy Resource Book, 2003.
Rolling AlongWheels and Axles
See 3rd Grade CORE Academy Resource Book, 2003.
Tool BoxTo be played similar to Fruit Bowl
- Research a simple or compound machine. Write a report detailing
when, where, why, how, and by whom the machine was invented.
The student may also include technological advances in the
machine since its original invention.
- Make a classroom book entitled The ABCs of Simple Machines.
Divide the students into groups of four. Instruct the students to
explore movements representative of simple machines. Each group will
become a compound machine. When the machine is turned on, one
part (one student) of the machine begins operating. In a sequential order,
each part (student) is activated by the part (student) next to them by
pushing or pulling on him/her.
Pantomime activities that involve a push, a pull, or push. The rest of
the class has to guess the activity and the force involved.
Simple Machine Hunt
Have the students, with the help of their family, identify and classify
simple machines found in and around their homes. Students record their
findings on the Simple Machine Hunt worksheet (pdf).
Have the students share this activity with their family and the
scientific principle involved.
Simple Machines Bingo
Family members take turns spinning the Simple Machine Bingo
Spinner (pdf) and marking a corresponding spot on his/her Simple
Machine Bingo Card (pdf) .
Mouse Trap Game
Purchase a Mouse Trap game for the class. Have the students take
turns taking it home to play with their family. Have the family work
together to write down the different pushes and pulls or simple machines
incorporated in the game.
Give each student a spoon labeled “Push,” a spoon labeled “Pull,”
and a spoon labeled “Push and Pull.” Instruct the student to hold up the
correct spoon(s) that identifies the force(s) being used in various
situations (e.g., hitting a baseball, sharpening a pencil in a manual crank
machine, opening the drapes, etc.).
Science Journal Writing
Have the students write in their science journals about each of the
simple machines and explain how each simple machine makes work