Tug of War game (photo by Resolingaire Pixabay)

A small child pushes an adult on a swing
(Photo by Slashme via Wikimedia)

Setting the Stage

A force can be considered a push or a pull upon an object. It can cause an object to speed up, slow down, change the direction of movement, remain in place or change shape. The most straightforward forces to understand are those in which physical contact is made with an object, such as pulling a sled or pushing against a door. Through exploration and identification of the forces of push and pull that can be applied to a simple object like a ping pong ball, this inquiry provides opportunities for students to observe, classify and compare the forces involved in familiar everyday activities such as pushing a swing, propelling a skateboard forward, or pulling a wagon and the forces of push and pull.

This inquiry could begin from:

  • experiences at the school or community playground. Discuss using questions such as:
    • “What did you do to make the swing move?”
    • “How does a teeter-totter move and change direction?”
    • “If someone wanted to swing higher, what would have to change about how the swing is made to move?”

    A yo-yo moves up and down
    (Photo by KateLeigh via iStock)


  • viewing a variety of images of opposite actions (e.g., up/down, open/close,walk/run, lift/drop, push/pull, smile/frown). Discuss using questions such as:
    • “I notice that you paired the pictures. How did you decide which pictures went together?”
    • “What are some other opposite actions that we could add to this collection?” (e.g., bend/straighten, attack/defend, move backward/move forward)

  • reading a book such as Motion: Push and Pull, Fast and Slow by Darlene Stille. Discuss using questions such as:
    • “What ways can things move?”
    • “What is an example of a pushing force? A pulling force?”
    • “What words might we use to describe motion?”
    • “What types of motions and forces are fun to experience?”
    • “What types of motions and forces might be scary or dangerous to experience?”

Materials and Preparation (Click to Expand)

Materials:

t-chart

Exemplar T-chart
(photo by Let’s Talk Science)

  • Ping pong ball – 1 per group
  • Straws – 3-4 per group (ensure 1 per student)
  • String – 1 piece per group, approximately 45 cm long
  • Craft stick – 1 per group
  • Plastic spoon – 1 per group
  • Plastic cup – 1 per group
  • Ruler – 1 per group, 15 cm (6 inch)
  • Plastic zip top bag – 1 per group
  • Chart paper
  • Hoops for Venn diagram
  • Science journal
notebook, pens, materials

Materials (photo be Let's Talk Science)

Preparation:

  • Source and fill plastic bags with the following materials – 1 ping pong ball, 1 straw per student, 1 piece of string, 1 craft stick, 1 plastic spoon, 1 plastic cup and 1 ruler. Create enough bags to provide one set of materials to each group of 3-4 students in your class. Note – For hygiene purposes, ensure that there is 1 straw for each student and discard the used straws after the inquiry.
  • Review the Sorting Mats Learning Strategy (e.g. T-Chart, Venn diagram) and share samples with students as possible ways to compare and record ideas about where they encounter pushes and pulls.

Exemplar Venn Diagram
(photo by Let’s Talk Science)

What To Do

Students use the Sorting Mats learning strategy and develop and apply the skills of Observing, Comparing & Contrasting and Sorting & Classifying as they explore the forces of push and pull acting on everyday objects.

Students:

  • use the bag of suggested materials to explore and observe all the ways they can move the ping pong ball back and forth across a table. Small groups of students seated across from each other at a desk or table are best.
  • compare and contrast observations about what happens, what is the same, and what is different between different types of pulls and pushes, etc. (e.g., students should conclude that a ping pong ball on a table can be made to change direction if a different type of force is applied - i.e., a push or a pull – and that the strength of the push or pull can make the ball go faster, change direction, or fall off the table).
  • sort and classify the information gathered about the different ways that the ping pong ball can be pushed and pulled using sorting mats or hoops, and record (in words, drawings or photos) the results of their sorting and classifying using a T-chart or a Venn diagram.
    • Educator supports (as necessary) with guiding questions about how to use a Venn diagram or T-chart.
  • communicate understanding of pushes and pulls as forces that can move objects in many different ways.

Assessment

Observe and document, using anecdotal comments, photos and/or video recordings, student’s ability to:

  • Observe - students make use of their senses to observe examples of forces of push and pull on the ping pong ball.
  • Compare & Contrast - students compare and contrast the different ways that the ball can be pushed and pulled.
  • Sort & Classify - students sort and classify things/actions that either exerts a push and/or a pull, or that need a push and/or a pull to work.
  • Record - students record examples of the forces of push and pull they observe.
  • Communicate - students share their understanding in a variety of ways using specialized vocabulary (e.g., force, push, pull, direction, opposite).

Co-constructing Learning

Students:
Saying, Doing, Representing

Educator Interactions:
Responding, Challenging

Students observe examples of the forces of push and pull on the ping pong ball.

  • “How many different ways can you push or pull the ping pong ball across the table?”
  • “How can this material or object be used to push or pull the ball?”
  • “The ping pong ball moved really quickly across the table! How did you make it go so fast?”

Students compare and contrast the forces of pull and push they observe.

  • “How is the push of the straw different from the push of the craft stick?”
  • “Does that pull/push seem as strong as this pull/push?”
  • “Are there as many ways to push the ball as there are to pull the ball?"

Students sort and classify the forces they observe as either pulls or pushes.

  • “If Jenna sends the ball back to you using the stick like a bat, is that a push or a pull?”
  • “How would you classify that movement?”
  • “Are all the push and pull forces caused by direct contact of an object on the ball?”
  • “Is unrolling the string that way caused by a push or a pull?”

Students record and communicate their understanding of forces and how the strength of a push or pull affects how an object moves.

  • “What did your investigations tell you about the forces of push and pull?” (objects move in the direction of the push/pull; the harder the push, the farther the object moves; the harder you pull, the faster the object moves)
  • “Is it easier to push or to pull an object? What makes you think that? What do our results show us?”

Cross-Curricular Connections

Literacy

  • Ask questions (e.g., to learn more about other forces such as friction and buoyancy)
  • Communicate learning in a variety of ways (e.g., using T-charts and Venn diagrams)
  • Use appropriate vocabulary (e.g., “We could push the car in a forward direction from behind. A tow truck could also pull the car forward from the front of the car. So I think both a push and a pull force can cause forward movement.”)

Mathematical Thinking

  • Compare the relative strength of different forces (e.g., “That stronger push was able to send the ping pong ball flying off the table.”)
  • Read primary data presented in graphs, charts, etc., and describe the data using comparative language (e.g., “There are three more examples of push than pull on the chart”)
  • Represent (e.g., using pictures, diagrams, graphs, tables, numbers, words, and/or symbols)

Physical Education

  • Developing manipulation skills by exerting force on objects or experiencing force from objects when sending, receiving, or retaining objects (e.g., throwing, catching, trapping, collecting, kicking, punting, dribbling, carrying, volleying, striking)
  • Developing effort awareness (e.g., thinking about how our body moves and exploring the forces we can create with our bodies)

Extending the Learning

If your students are interested in learning more, the following may provoke their curiosity:

Playground swing
(Photo by summa via Pixabay)

  • Extend the exploration of pulls and pushes to other areas inside and outside of the classroom or at home, observing and recording examples of things that exert a push and/or a pull, or that need a push and/or a pull to work.

  • Explore the push and pull of magnets. Conduct an inquiry such as Magnificent Magnets where students can explore magnets as a non-contact force that causes movement.

  • Friction is another direct contact force that students can easily understand and explore. Friction is a force that slows or resists motion. Provide opportunities for students to continue exploring motion by conducting an inquiry such as How Surfaces Affect Motion.

Child pulling a wagon
(Photo by Biscan via Wikimedia)

Child pushing a mop
(Photo by StockSnap via Pixabay)