Everyday Polymers

Contributor
University of Colorado Boulder, Teach Engineering
Type Category
Instructional Materials
Types
Lesson/Lesson Plan
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

In this lesson, students understand what polymers are and the role that they play in their everyday life. After gaining the initial understanding of polymers, students create and test a polymer (silly putty) to reinforce understanding of polymers. Students then make connection on microscopic level structure to macro level properties such as highest bounce or longest stretch by changing the ratios of material to get silly putty with desired attributes through engineering design. This lesson helps students understand that desired properties in a designed material are a result of manipulation of structure at the molecular- level. A particular strength of this lesson is connection with the engineering design.

Intended Audience

Educator and learner
Educational Level
  • High School
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

HS-PS2-6 Communicate scientific and technical information about why the molecular-level structure is important in the functioning of designed materials.

Clarification Statement: Emphasis is on the attractive and repulsive forces that determine the functioning of the material. Examples could include why electrically conductive materials are often made of metal, flexible but durable materials are made up of long chained molecules, and pharmaceuticals are designed to interact with specific receptors.

Assessment Boundary: Assessment is limited to provided molecular structures of specific designed materials.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
Students gain understanding of everyday polymers by listing and looking at different consumer items made of polymers. Students then delve deeper into the molecular structure of polymers and the role of cross linkages in making a polymer rigid by creating a polymer and manipulating its properties (stretchability, bounciness). This engineering design helps students see explicitly the impact that molecular-level structure (number of polymer chains, cross linkages) have on the bounciness and rigidity of the polymer. A manipulative with pipe cleaners and beads may strengthen visualization of impact of molecular structure in terms of polymer chains and cross linkages on the properties such as rigidity of the polymer.

Science and Engineering Practices

This resource appears to be designed to build towards this science and engineering practice, though the resource developer has not explicitly stated so.

Comments about Including the Science and Engineering Practice
Students construct an explanation for the structure and properties of everyday polymers. Students then make silly putty with desirable properties of bounciness and stretchiness and construct an explanation for how desired properties in a designed material are result of structure at the molecular level.

Disciplinary Core Ideas

This resource was not designed to build towards this disciplinary core idea, but can be used to build towards it using the suggestions provided below.

Comments about Including the Disciplinary Core Idea
This lesson does a good job of connecting molecular level structure (polymer chains, cross linkages) to properties such as bounciness and stretchability. However, for more explicit alignment with DCI, this needs to be explained in terms of attractive and repulsive forces. Explaining cross linkages as bonding resulting from such forces will have a stronger alignment with DCI.

Crosscutting Concepts

This resource appears to be designed to build towards this crosscutting concept, though the resource developer has not explicitly stated so.

Comments about Including the Crosscutting Concept
This lesson explicitly covers the cross cutting concept of Structure and Function by having students examine the properties of some everyday polymers, then make their own polymer to investigate the properties. Students further improve their silly putty for bounciness and stretchability to see that molecular structure impacts properties of this designed material.

Resource Quality

  • Alignment to the Dimensions of the NGSS: This lesson aligns well to the three dimensions of NGSS, addressing PE HS-PS2-6 around properties of designed material and their connection to molecular-level structure. Students engage in design thinking by modifying their method for making silly putty to get desired properties. This activity reinforces the idea of manipulation of designed materials to get desired properties. Having a component of engineering design along with physical science PE is a particular strength of this lesson.

  • Instructional Supports: This lesson provides excellent instructional support and scaffolding in terms of vocabulary, power points, worksheets, detailed lab procedure as well as detailed lesson background for the teacher to do things before the lesson. The background information is particularly strong in providing information and guidance onNot many teachers are well-versed in designed materials and polymers.

  • Monitoring Student Progress: While the lesson provides good scaffolding, there are not many opportunities for formative assessment. Incorporating formative assessments during the lesson such as identify the polymers from a number of polymers provided or identify which polymers will have more cross linkages based upon rigidity and drawing their molecular structure could be useful.

  • Quality of Technological Interactivity: There is no technological interactivity.