Teaching Sequence

Work through this resource material in the following sequence:

15 minutes

Tune In: What is plastic?

20 minutes

Find Out: Exploring different plastics

20 minutes

Take Action: Communicating plastic recycling

5 minutes

Reflection

Learning intentions

Students will:

compare the physical and chemical properties of different types of plastic.

Success criteria

Students can:

identify different types of plastic based on their properties
explain why plastic needs to be separated into different types to be able to be recycled.

Tune In: What is plastic?

Step 1

Introduce the lesson by explaining to students that they will be exploring plastic. Direct the students to the KWL section of the Student Worksheet. Ask them to fill out what they already think they know about plastic and what they don’t yet know (wonder) about plastic. If your students need prompting, ask them to think about:

how plastic is made
where they think plastic comes from
when we first started using plastic
what we use plastic for
why we choose plastic over other materials.

Step 2

Share the following video with the class, and as they watch, invite students to record any additional thoughts, questions or anything they find interesting or important:

Plastics 101 | National Geographic (youtube.com/watch?v=ggh0Ptk3VGE)

Note: This lesson is primarily concerned with the content featured in the first half of this video (0:00 to 2:52), so if time is limited, you can just watch this section. However, watching the whole video gives a complete picture of the problem with plastic and some of the solutions. Although these points may not be explored in depth in this lesson, they help set the context for why an investigation into plastics is essential.

Select 3-4 students to share one of their thoughts or questions with the class.

Step 3

Explain to your students that they will now explore the classroom and find out just how many different uses for plastic we have.

Distribute a copy of the Student Worksheet to each student. Invite students to spend 5-10 minutes moving around the classroom looking for plastic objects in your classroom (this could include desks, chairs, devices, lunch boxes, water bottles, stationary, clothes, cups, etc.). They can use the space provided on the Student Worksheet to record the plastic objects they find.

Once complete, invite 3-4 students to share what they found with the class. Focus particularly on the types of plastic that were recorded: were students able to identify chemical compositions (e.g. the plastic codes represented in the video)?

Find Out: Exploring different plastics

Step 1

Ask your students why they think we have so many different types of plastic.

Suggested answer: Different types of plastic have different properties that make them more or less suitable. For example, some plastics are rigid, some are flexible, some are transparent, and some are opaque.

Step 2

Explain to students that they will now investigate the physical and chemical properties of different types of plastic. The different types of plastic will be defined by their plastic identification codes. Provide students with the Plastic Identification Code Cards and explain that different types of plastic have different properties, which makes them suitable for different purposes. Show the students the PET bottle. Ask them to look at the PETE (PET) card and identify which properties make it suitable for creating drink bottles. They might suggest:

being lightweight and strong makes it ideal for shipping
being resistant to moisture means it doesn’t leak
being resistant to gas means it can keep beverages carbonated
being clear means consumers can see the beverage they are choosing
low softening point means it is easy to mould
high melting point means accidental heat exposure won’t damage the bottle.

Step 3

Now it’s your students’ turn. Have them return to the plastics they found earlier and use the cards to identify the plastic types. If the plastic was not labelled with an identification code, see if they can identify what type of plastic they think it is, based on the properties and what it is being used for.

Once they have identified the plastic type, they will need to look at the properties of this plastic listed on the card, and propose why this specific type of plastic was used for this purpose.

Learning support: Choose specific examples of plastic with easily identifiable codes, and work together as a class to propose why this item was made from this plastic.

Step 4

Once complete, invite pairs to share what they learned about the plastic types they investigated with other students. You could invite pairs to team up with other pairs to share or nominate volunteers to share their research with the class.

Literacy extension: Some students might notice that all of these plastics have ‘poly’ in the name. You could provide students with the Plastic Polymers Factsheet. The factsheet explains that the term ‘polymer’ is derived from two Greek words: poly, meaning ‘many,’ and meros, meaning ‘parts’. You can imagine a polymer as a chain, where each link represents a ‘mer’ (a single unit). From here, students can explore the other parts of the plastic names (e.g. polypropylene) to see what these names tell us about the material.

Take Action: Plastic pathways

Step 1

Now that we know more about the different types of plastic let’s explore their life cycles. Using the Plastic Pathways Worksheet as a guide, students will need to explore the lifecycle of a specific plastic type. Students will need to choose a type, and using online research, students can explore the lifecycle of a specific item made from this plastic type. They will investigate

how this type of plastic is sourced
how the item is made
what happens to the item if it goes to landfill
what happens to the item if it is recycled
what the process is for recycling this item in their local area.

Numeracy extension: What are we saving by recycling this material? Some people theorise that we already have all the plastic we need if only we recycled all of it. Ask students to estimate the cost of making their item from new materials vs recycled materials.

Step 2

Consider providing students with a forum for sharing their completed Plastic Pathways, such as a Gallery Walk (pz.harvard.edu/resources/gallery-walk).

Reflection

Invite students to return to their KWL charts, reflect on their K and W columns, and add notes to the L column. Encourage students to consider a world in which all plastics were recyclable and add any further reflections to their W column.

Visy Education - What Is Plastic?

Summary

Lesson Guides and Printables

Visy Education - What Is Plastic?

Summary

Lesson Guides and Printables