80 minutes for classroom activities
Often times students have trouble understanding how friction is an opposing force to motion. With this design experiment, students can witness how friction plays a key role in the motion of an object. The goal of this experiment will be for students to evaluate the current friction of tennis sneakers and to then design a model to increase the friction of the shoe. Part of this case study will involve students researching why tennis players need additional friction on the soles of their shoes. For example, a student can deduce that if friction is not present, then a tennis player can slide across the tennis court during a tennis match. The second part of the lesson will involve them making a model of their new shoe for mass reproduction. This unit coincides seamlessly with many state standards covering: force, mass, and motion.
Nature of Science
Standard 12. Level III. Understands the nature of scientific inquiry
1. Knows that there is no fixed procedure called "the scientific method," but that investigations involve systematic observations, carefully collected, relevant evidence, logical reasoning, and some imagination in developing hypotheses and explanations
2. Understands that questioning, response to criticism, and open communication are integral to the process of science (e.g., scientists often differ with one another about the interpretation of evidence or theory in areas where there is not a great deal of understanding; scientists acknowledge conflicting interpretations and work towards finding evidence that will resolve the disagreement)
3. Designs and conducts a scientific investigation (e.g., formulates hypotheses, designs and executes investigations, interprets data, synthesizes evidence into explanations)
4. Identifies variables (e.g., independent, dependant, control) in a scientific investigation
5. Understands why only one variable (independent) can be manipulated at a time and that all other variables must be controlled during the investigation
Standard 10. Level III. Understands forces and motion
3. Knows that an object’s motion can be described and represented graphically according to its position, direction of motion, and speed
4. Understands effects of balanced and unbalanced forces on an object’s motion (e.g., if more than one force acts on an object along a straight line, then the forces will reinforce or cancel one another, depending on their direction and magnitude; unbalanced forces such as friction will cause changes in the speed or direction on an object’s motion)
5. Knows that an object that is not being subjected to a force will continue to move at a constant speed and in a straight line
Common Core State Standards
English Language Arts Standards Writing
Production and Distribution of Writing:
- CCSS.ELA-LITERACY.WHST.6-8.4 Produce clear and coherent writing in which the development, organization, and style are appropriate to task, purpose, and audience.
- CCSS.ELA-LITERACY.WHST.6-8.5 With some guidance and support from peers and adults, develop and strengthen writing as needed by planning, revising, editing, rewriting, or trying a new approach, focusing on how well purpose and audience have been addressed.
- CCSS.ELA-LITERACY.WHST.6-8.6 Use technology, including the Internet, to produce and publish writing and present the relationships between information and ideas clearly and efficiently.
Research to Build and Present Knowledge:
- CCSS.ELA-LITERACY.WHST.6-8.7 Conduct short research projects to answer a question (including a self-generated question), drawing on several sources and generating additional related, focused questions that allow for multiple avenues of exploration.
- CCSS.ELA-LITERACY.WHST.6-8.8 Gather relevant information from multiple print and digital sources, using search terms effectively; assess the credibility and accuracy of each source; and quote or paraphrase the data and conclusions of others while avoiding plagiarism and following a standard format for citation.
- CCSS.ELA-LITERACY.WHST.6-8.9 Draw evidence from informational texts to support analysis, reflection, and research.
English Language Arts Standards: Speaking and Listening
Comprehension and Collaboration:
- CCSS.ELA-LITERACY.SL.6-8.1 Engage effectively in a range of collaborative discussions (one-on-one, in groups, and teacher-led) with diverse partners on grade level topics, texts, and issues, building on others' ideas and expressing their own clearly.
- CCSS.ELA-LITERACY.SL.6-8.1.A Come to discussions prepared, having read or researched material under study; explicitly draw on that preparation by referring to evidence on the topic, text, or issue to probe and reflect on ideas under discussion.
- CCSS.ELA-LITERACY.SL.6-8.2 Analyze the purpose of information presented in diverse media and formats (e.g., visually, quantitatively, orally) and evaluate the motives (e.g., social, commercial, political) behind its presentation.
- CCSS.ELA-LITERACY.SL.8.3 Delineate a speaker's argument and specific claims, evaluating the soundness of the reasoning and relevance and sufficiency of the evidence and identifying when irrelevant evidence is introduced.
Presentation of Knowledge and Ideas:
- CCSS.ELA-LITERACY.SL.6-8.4 Present claims and findings, emphasizing salient points in a focused, coherent manner with relevant evidence, sound valid reasoning, and well-chosen details; use appropriate eye contact, adequate volume, and clear pronunciation.
- CCSS.ELA-LITERACY.SL.6-8.5 Integrate multimedia and visual displays into presentations to clarify information, strengthen claims and evidence, and add interest.
- CCSS.ELA-LITERACY.SL.6-8.6 Adapt speech to a variety of contexts and tasks, demonstrating command of formal English when indicated or appropriate. (See grade 8 Language standards 1 and 3 here for specific expectations.)
English Language Arts Standards: Science & Technical Subjects
Key Ideas and Details:
- CCSS.ELA-LITERACY.RST.6-8.1 Cite specific textual evidence to support analysis of science and technical texts.
- CCSS.ELA-LITERACY.RST.6-8.2 Determine the central ideas or conclusions of a text; provide an accurate summary of the text distinct from prior knowledge or opinions.
- CCSS.ELA-LITERACY.RST.6-8.3 Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
Craft and Structure:
Integration of Knowledge and Ideas:
- CCSS.ELA-LITERACY.RST.6-8.4 Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 6-8 texts and topics.
- CCSS.ELA-LITERACY.RST.6-8.5 Analyze the structure an author uses to organize a text, including how the major sections contribute to the whole and to an understanding of the topic.
- CCSS.ELA-LITERACY.RST.6-8.6 Analyze the author's purpose in providing an explanation, describing a procedure, or discussing an experiment in a text.
- CCSS.ELA-LITERACY.RST.6-8.7 Integrate quantitative or technical information expressed in words in a text with a version of that information expressed visually (e.g., in a flowchart, diagram, model, graph, or table).
- CCSS.ELA-LITERACY.RST.6-8.8 Distinguish among facts, reasoned judgment based on research findings, and speculation in a text.
- CCSS.ELA-LITERACY.RST.6-8.9 Compare and contrast the information gained from experiments, simulations, video, or multimedia sources with that gained from reading a text on the same topic.
Range of Reading and Level of Text Complexity:
- CCSS.ELA-LITERACY.RST.6-8.10 By the end of grade 8, read and comprehend science/technical texts in the grades 6-8 text complexity band independently and proficiently.
- design a plan to change the tread of a tennis sneaker to increase friction
- learn that friction is a force that opposes motion and makes it difficult for that object to move across a surface
- learn that friction depends on two things: the surface types and the force pressing those surfaces together
- learn that we experience friction everyday and it helps and hinders things that we do
- tennis shoe (type of shoe worn while playing tennis) (Note: The teacher can modify the type of shoe, with one that is more easily accessible in their school, for instance, football cleats.)
- spring scale
- data table
- various art and craft supplies to be used in construction of the models
- contact: the physical coming together of two or more things
- drag: pull, as against a resistance
- force: a powerful effect or influence
- friction: the resistance encountered when one body is moved in contact with another
- motion: movement; a natural event that involves a change in the position or location of something
- newton: unit of measurement; the absolute measure of force
- surface: the outer boundary of an artifact or a material layer constituting or resembling such a boundary
1. Teacher will ask students to create a concept map, in which they define friction in their terms. For their concept map, they must: define friction; draw a picture of it; and give an example of it. Students will then be asked to share responses with the class. The teacher will use this moment to introduce the major concept of “friction”: the force that acts in the opposite direction to motion.
2. The teacher will then ask students to use some of their current scientific understandings to show how friction can be beneficial and harmful to us during everyday events, i.e., driving, walking, etc.
3. Students will then form groups consisting of a maximum of four members:
a. A Reporter—This person writes down all data for the group.
b. Team Manager—This person communicates any questions/concerns to the teacher and keeps the group on task. This person is also in charge of conducting background research for the group, which includes finding definitions.
c. Investigator(s)—These students conduct the experiment. This will require the collaborative learning model as students will need each other for the experiment to run smoothly (i.e., one person will need to weigh the tennis shoe, while the other person prepares it to be measured using spring scales).
4. After students have formed their groups, they will then measure the mass of the sneaker. The students will need to add a mass of 5000 g, so that the mass is evenly distributed in the sneaker.
5. Students will then record the various frictions for the sneaker in the Data Collection Table.
a) To measure “Starting Friction”: students will attach the spring scale to the back of the sneaker and pull the scale in the opposite direction (when the shoe begins to move this is the recorded “Starting Friction” - in newtons).
b) To measure “Sideways Stopping Friction”: students will attach the spring scale to the side of the sneaker and pull the scale in the opposite direction - away from the shoe (when the shoe begins to move this is the recorded “Sideways Stopping Friction” - in newtons).
c) To measure “Forward Stopping Friction”: students will attach the spring scale to the front of the sneaker and pull the scale in the opposite direction - away from the shoe (when the shoe begins to move this is the recorded “Forward Stopping Friction” - in newtons).
6. Students will begin with the first step in the design process, which is to define and recognize their problem, based on the data that they have collected. (Example: I have a shoe that is used for tennis and I need to increase the friction, so that it can be used in another sport.)
7. After students have defined their problem they must analyze the data that supports the idea that this problem exists. In order to continue, students must have substantial proof that this is a problem worth solving. In this case, students must prove to the teacher that it would be dangerous to use tennis shoes (Sneaker A) to play football or soccer (Student-created Sneaker B). Students would have to further explain why this would pose a problem (i.e. too much friction or too little friction).
8. The students will have to define their variables in order to go to the next stage of the design process:
a. What are current friction forces of other shoes? (published by shoe companies)
b. What is the estimated cost to convert your model to one that has more friction?
c. How can their product survive in a competitive market?
d. What scientific content supports that there is a need for your product? (i.e., Increased friction would allow a football player to stop easily while running.)
e. In this step, students will complete several sketches of their design, but will not go on to create prototypes until they have this work checked by the teacher.
9. In the next step, students will continue with the design process and will create a prototype of their design. Students will also implement their designs and evaluate them for any modifications.
10. Students will then present their findings to their peers. Students must present their designs in several formats:
a) Sketch of new shoe (that has increased friction)
b) Prototype and subsequent three-dimensional designs
c) Oral presentation
11. Finally, students and teacher will provide feedback, and one final homework assignment will be for the student to reflect on the process it took to complete this project. Students must also detail several barriers, and explain how they would complete this project differently, if they had an opportunity to do so.
Students will complete an analysis of their final designs and use their findings to analyze the following questions:
1. How does the surface type influence the amount of friction there is? If you used a different material for your sole, would you have yielded different results?
2. What is the relationship between the size and weight of an object and the amount of friction that is present? Do you need to make a shoe with more friction if the player is a different size?
3. Use your findings to deduce, how friction can be both a positive and negative aspect in our daily lives.
4. Other sports, such as soccer and football, also utilize friction. How do you think the soles of their shoes are different? In these cases how does friction help these players?
5. What was another way you could have reduced the friction in your activity today? How could you have increased it?
6. Could you live a life with no friction? Explain what activities would be harder for you to do? Which activities would be easier?
Enrichment Extension Activities
Students can continue their investigation at home with various types of shoes and compare the differences in friction, using a borrowed or created spring scale. Directions for making your own spring scales can be found on: