Living With Plastics (Developed by SEPUP)
There are many different types of materials used to produce the same product.
Which is best?
What are the trade-offs in selecting one material over another?
In this module, students address these questions by focusing on the development and use of plastic. They investigate the properties of different plastics and read about the history of plastics development. The students are then introduced to the basics of polymer chemistry and model the effect of crosslinking on polymer properties. They also explore the properties of natural polymers and relate these properties to their everyday uses. In the final activity, students apply their knowledge of plastics to evaluating competing claims about the usefulness of plastics.
The embedded assessment system focuses on students’ ability to use evidence and identify trade-offs.
This module includes a Teacher's Guide
Accommodates five classes, each with 8 groups of four students
More Info
This module has 8 activities which will require 12 to 16 ~50-minute class periods to complete.
1. Evaluating Materials
Students evaluate the use of aluminum, glass, and plastic for producing a soft drink container. They discuss the advantages and disadvantages of each material as they analyze information on its production, energy costs, and recyclability. They use this evidence to select one material and then discuss the trade-offs of their decision.
2. Materials Use Over Three Generations
Students survey their parents and grandparents (or other adults of approximately the same age) to investigate how the materials used to make everyday products have changed over three generations. Students then read about how plastics were developed and produce a creative writing piece about daily life before the development of plastics.
3, Properties of Plastic Polymers
Students explore the properties of four common plastics and examine the relationship between these properties and the uses of these plastics. They apply what they learn to determine the identity of unknown plastic samples.
4. Cross-Linking Polymers
Students cross-link polyvinyl alcohol with sodium borate to produce a polymer similar to the one known commercially as Slime. They observe and compare the properties of the reactants with the product. Students are introduced to the concept of polymers as a chain of smaller molecules, or monomers. They read about the chemistry of polymers and the effect of cross-linking on the properties of polymers.
5. Modeling Polymers
Students study the structure of polymer molecules by making models of polymers with paper clips. Understanding the structure of the polymer molecules helps students understand the properties of polymers. The class acts as a polymer model, with student pairs representing monomers. Students then identify polymers used in daily life.
6. Natural and Synthetic Polymers
Students learn about natural polymers by investigating some of the properties of both natural and synthetic polymers. They test the strength, elasticity, and buoyancy of cotton, paper, low-density polyethylene, and polyester. Students then relate the use of these four polymers in everyday life to their properties.
7. The Energy Cost of Making Polymers
Students calculate the energy needed to produce paper, plastic, and cotton grocery bags. They consider how grocery bags are used in everyday life and analyze the energy costs of all three materials. Students use the results of this investigation and of Investigation 6, “Polymer Properties,” to decide which type of grocery bag to use.
8. Evaluating Plastic
Students read information about plastics provided by two fictitious groups. They share their own opinions as they evaluate the truth of the claims. Each student is then asked to summarize his or her knowledge of plastics by writing a encyclopedia entry on plastics.
Scientific Concepts
- Plastics can be differentiated based on their physical properties, including flexibility, hardness, and buoyancy. The properties of a material determine how it can be used.
- Plastics are made primarily from the hydrocarbons in petroleum and are part of a group of chemicals known as polymers.
- The production of materials has hidden costs, such as energy use.
- Gathering relevant evidence is essential for thoughtful inquiry and good decision making.
- Making decisions about complex issues often involves trade-offs and evaluating issues requires an analysis of both risks (costs) and benefits.
Guides & Student Sheets
Our kits and modules provide you with everything you need so you can open, review, and teach the material confidently the next day.
- Full downloadable Teacher Guide with background information, detailed instruction, example data and answers
- Downloadable Student Sheets with age appropriate background information, full procedure(s), and analysis questions
- All materials necessary to carry out the investigation
- Safety Data Sheets
Module Components
- 1 Teacher’s Guide with reproducible masters for Student Sheets
- 500 Silver paper clips
- 100 Colored paper clips
- 90 Cotton fabric squares, 2 x 2"
- 90 Polyester fabric squares, 2 x 2"
- 90 White LDPE plastic squares, 2 x 2"
- 90 Brown paper squares, 2 x 2"
- 80 Salt packets
- 32 30 mL graduated cups
- 24 Vials with caps
- 24 9 oz plastic cups
- 16 Plastic spoons
- 8 Drop control bottles of denatured Ethanol
- 8 Drop control bottles of Sodium Borate solution, 4%
- 8 Drop control bottles of “Water", empty
- 8 Drop control bottles of Blue Food Coloring solution
- 8 180 mL bottles of Polyvinyl Alcohol solution, 4%
- 8 60 mL wide-mouth bottles
- 8 Material Data Cards, sets of 24
- 8 Forceps
- 8 Droppers
- 1 180 mL bottle of Acetone
- 1 Bag of plastic strips, 45 each of blue green red and yellow
- 1 Bag of plastic strips, 10 each of clear, orange, black and white
- 1 Bag of plastic squares, 45 each of blue green red and yellow
- 1 Bag of plastic squares, 10 each of clear, orange, black and white
- 1 MSDS (Material Safety Data Sheets)