The Arizona STEM Acceleration Project

Investigating the Effects of Balanced and Unbalanced Forces

on the Motion of Objects: Lesson 2

Investigating the Effects of Balanced and Unbalanced Forces on the Motion of Objects:

Lesson 2

A 5th Grade STEM Lesson

Robyn Yewell

Spring 2023

Notes for Teachers

The agenda has suggested time allotments. Please modify for the unique needs of your own classroom. This lesson may take the suggested 70 minutes or longer depending on your classroom schedule.

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Provide time for your students to really think about the phenomenon and accept all student ideas as valid. This will provide you with insight into what your students think, helping to address misconceptions.

List of Materials for Lesson 2

• An assortment of various objects such as paper, balls, books, etc.
• index cards
• copy paper, 1 sheet per student
• 8 ½ by 11 inch white paper, one per group
• Discourse Primer Ambitious Science Teaching
• Rulers
• Post-it Notes (one pad per group)
• Pencils
• Table or Desk Surface
• STEM Teaching Tool #41 Prompts for Integrating Crosscutting Concepts Into Assessment and Instruction
• Colored Pencils, Crayons, or Markers
• Computer to display Google Slide Deck or pictures of the “Wonderland of Rocks” at Chiricahua National Monument near Willcox, Arizona
• Class whiteboard and marker or large post-it note sheets

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Standards

Arizona Science Standards:

5.P3U1.4 Obtain, analyze, and communicate evidence of the effects that balanced and unbalanced forces have on the motion of objects.

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Science & Engineering Practices:

● develop and use models

● analyze and interpret data

● construct explanations and design solutions

● engage in argument from evidence

● obtain, evaluate, and communicate information

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Arizona ELA Standards:

5.RI.9 Integrate information from several texts on the same topic in order to write or speak about the subject knowledgeably.

5.W.4 Produce clear and coherent writing in which the development and organization are appropriate to task, purpose, and audience.

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Arizona 5th Grade ELA Standards: (continued)

5.SL.1 Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade 5 topics and texts, building on others’ ideas and expressing their own clearly. b. Follow agreed-upon rules for discussions and carry out assigned roles. c. Pose and respond to specific questions by making comments that contribute to the discussion and elaborate on the remarks of others. d. Review the key ideas expressed and draw conclusions based on information and knowledge gained from the discussions.

Arizona 5th Grade Math Standards:

5.MD.A.1 Convert among different-sized standard measurement units within a given measurement system, and use these conversions in solving multi-step, real-world problems.

Objective(s):

• Students will understand the concepts of balanced and unbalanced forces.
• Students will be able to identify the effects that balanced and unbalanced forces have on the motion of objects.
• Students will be able to analyze and communicate evidence of the effects of balanced and unbalanced forces on the motion of objects.

Agenda (70 minutes)

Lesson 2:

Review of ideas from Lesson 1 (5 minutes)

Observations and Measurements of Balanced and Unbalanced Forces (20 minutes)

Introduction to Model-Based Inquiry (30 minutes)

Reflection (15 minutes)

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Why do the “Wonderland of Rocks” at Chiricahua National Monument near Willcox, Arizona stay in place?

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https://www.flickr.com/photos/alanenglish/6826578509

Observations and Measurements of Balanced and Unbalanced Forces

• Start by asking the students if they have ever played a game of tug-o-war. Ask them what happens when the two teams are evenly matched and what happens when they aren’t. Watch the video and ask the students what they have observed. Is this an example of balanced or unbalanced forces? Why?

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• Next, split the students into small groups of no more than 2-3 students per group. Have them pick from the assortment of items, placing it on the table, trying to move it. Have each student sketch a model of what they see and write any observations or questions that they may have. What makes the object stay in place? Are there balanced forces acting on this object? If so, what are they? Record student ideas on whiteboard or large post-it note paper.

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• Provide an index card to each student group. Instruct the students to place it on top of their object. Have each student continue to sketch the model of what they see and write any observations or questions that they may have. Tell the students to use a pencil to push down lightly on the index card, but not too hard. Students should add what is happening to their sketch using both words and pictures. Discuss what is happening. Does the item move a little and stop? If so, record the measurements in cm using a ruler. Is this an example of balanced or unbalanced forces? Why?

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• Finally, ask the students to try moving the object with the index card by pushing it from side to side. Discuss how the object moves in the direction that they are pushing it. Have students add what happened to their sketches. Ask the students if this is an example of an unbalanced or balanced force? Why?

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Introduction to Model-based Inquiry

• The goal of this introduction is to bring out students’ initial ideas and experiences that they may have with the phenomenon or a related phenomenon. Students will be developing an initial hypothesis (initial explanations) and keep track of their thinking with a public record.

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• Create groups for students to work in throughout the unit. (3-4 students per group)

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• In small groups, ask students to come up with an initial hypothesis (written in complete sentences if possible) to answer the driving question, “Why do the “Wonderland of Rocks” at Chiricahua National Monument near Willcox, Arizona stay in place?”

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• Prompt: Based on what you have seen so far and your experience with balanced and unbalanced forces in general, what do you think causes the Wonderland of Rocks at Chiricahua National Monument to stay in place? And why do you think it would continue to rest in the same place or move?

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• Facilitate a whole class share out of groups’ initial hypothesis and write them on the ‘Initial Hypothesis’ public record.

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(Modified from MBI: Model based-inquiry https://sites.google.com/view/modelbasedinquiry/template/stage-descriptions?authuser=0)

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https://commons.wikimedia.org/wiki/File:Chiricahua_balanced_rock.jpg

Introduction to Model-based Inquiry

• In this part, students will choose an initial hypothesis to work on and create an initial model as a group. Please note that the most important part of the modeling process will be the discussion about what will be in the model and why.

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https://www.flickr.com/photos/alanenglish/6785477259

Photo by Allison Shelley/The Verbatim Agency for American Education: Images of Teachers and Students in Action

Reflection

• When groups have finished their initial model, lead a whole group discussion on what the students noticed, thought, or wondered, using STEM Teaching Tool #41 for support if needed with Prompts for Integrating Crosscutting Concepts Into Assessment and Instruction.

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• Wrap up Lesson 2 with a gallery walk using the models that the student groups created, using the tips and variations for success.

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• Have students return to their original groups and read their feedback. Collect student models and keep in a safe space for Lesson 3.

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http://www.pz.harvard.edu/sites/default/files/Gallery-Walk.pdf

Differentiation

• If students need extra support in reading or writing, ask them to give feedback during the gallery walk verbally.

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• Provide students with a scribe if needed.

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• Allow students to draw pictures instead of writing sentences to convey their thoughts.

Remediation

Extension/Enrichment

• Play a game of tug-o-war with the kids or split the class into smaller groups and have them play against each other.

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• Go on a scavenger hunt around school looking for balanced and unbalanced forces.

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• Have students work in pairs or small groups using different objects to create their own examples of balanced and unbalanced forces, Have them present their examples to the class and explain why they are examples of balanced or unbalanced forces.

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