Lesson plan: Why is only 9% recycled? (ages 12–14)

Lesson overview

• Title: Why is only 9% recycled? Plastic, limited resources and the recycling gap
• Age band: 12–14 (England Years 7–9 / KS3; US Grades 6–8; Australia Years 7–9)
• Duration: 60 minutes
• Subject: Science (Chemistry) with Geography, Design and Technology and Citizenship links
• Made by: No Plastic Today. Funded by: No Plastic Today (no sponsors, no industry funding). Licence: CC BY 4.0.

Learning objectives

• I can explain where plastic comes from (crude oil and gas) and why that makes it a limited resource.
• I can read the resin identification codes (1–7) and explain why sorting matters for recycling.
• I can interpret real data on what happens to plastic waste and explain why recycling rates are low.
• I can design a method to monitor plastic waste in my school and propose one way to reduce it.

Curriculum codes

• England National Curriculum Science KS3 Chemistry "Earth and atmosphere": the Earth as a source of limited resources and the efficacy of recycling. KS3 Geography: how human and physical processes interact to influence and change landscapes and environments; human reliance on natural systems. KS3 Design and Technology: evaluate the environmental impact of products. KS3 Citizenship: taking responsible action.
• Next Generation Science Standards (NGSS): MS-ESS3-3 (apply scientific principles to design a method for monitoring and minimising a human impact on the environment); MS-ESS3-4 (construct an argument supported by evidence for how increases in human population and per-capita consumption of natural resources impact Earth's systems); MS-ETS1-1 (define the criteria and constraints of a design problem).
• Australian Curriculum v9: Science Year 7 Earth and space sciences (renewable and non-renewable resources) (verify code on v9.australiancurriculum.edu.au); Year 8 Chemical sciences (verify); Geography Year 7 "Water in the world" (verify); Design and Technologies Years 7–8 (sustainability of materials); Sustainability cross-curriculum priority.
• International Baccalaureate (IB) Middle Years Programme (MYP): Sciences Criterion D (reflecting on the impacts of science); global context "Globalization and sustainability".

Materials

• Seven clean plastic items, one per resin code: 1 PET drinks bottle, 2 HDPE milk bottle, 3 PVC (e.g. a piece of pipe or blister pack), 4 LDPE bread bag, 5 PP yoghurt pot or bottle cap, 6 PS (polystyrene) cup or tray, 7 "Other" (a crisp packet or a multi-layer pouch).
• Resin code key (a one-page handout: code, polymer name, common uses, "is it widely recycled where we live?").
• Data card A, "All the plastic ever made": 8,300 million tonnes produced from 1950 to 2015; of the 6,300 million tonnes that became waste, 9% was recycled, 12% was burned and 79% went to landfill or into the environment (Geyer, Jambeck and Law, Science Advances, 2017: doi.org/10.1126/sciadv.1700782).
• Data card B, "Plastic waste in 2019": about 353 million tonnes of plastic waste; 9% recycled, 19% burned in incinerators, about 50% buried in managed, lined landfill sites, and 22% mismanaged (dumped, burned in the open or leaked into the environment) (Organisation for Economic Co-operation and Development (OECD) Global Plastics Outlook, 2022: oecd.org/en/publications/global-plastics-outlook_de747aef-en.html and press release oecd.org/en/about/news/press-releases/2022/06/global-plastic-waste-set-to-almost-triple-by-2060.html).
• Data card C, "It depends where you are": US post-consumer plastic recycling about 5–6% in 2021 (Beyond Plastics: beyondplastics.org/publications/us-plastics-recycling-rate) and EU plastic packaging recycling 41% in 2022 (Eurostat: ec.europa.eu/eurostat/web/products-eurostat-news/w/ddn-20241024-3).
• Data card D, "Who lacks a bin?": about 52 million tonnes of plastic entered unmanaged systems in 2020; 57% of it was burned in the open; 1.2 billion people have no waste collection at all (Cottom, Cook and Velis, Nature, 2024: doi.org/10.1038/s41586-024-07758-6).
• Data card E, "Growth": world plastic production rose from about 2 million tonnes in 1950 to about 460 million tonnes in 2019 (Our World in Data, using OECD and Geyer data: ourworldindata.org/plastic-pollution), and is set to nearly triple by 2060 without new policy (OECD, 2022: oecd.org/en/about/news/press-releases/2022/06/global-plastic-waste-set-to-almost-triple-by-2060.html).
• Monitoring-method planning sheet (question, what to count, where, when, how often, how to record, how to check it is fair).
• Exit ticket slips.

Starter (8 minutes)

• Show a lump of coal, a bottle of cooking oil and a plastic bottle (or images). Ask: "Which of these is the plastic bottle most closely related to?" Establish that most plastics are made from crude oil and natural gas, and that oil and gas are finite. About 12% of the world's oil goes into petrochemicals such as plastics (International Energy Agency, The Future of Petrochemicals, 2018: iea.org/reports/the-future-of-petrochemicals).
• Pose the big question on the board: "If plastic is made from a limited resource, why do we recycle so little of it?"

Main activity (40 minutes)

• Part 1, sort by code (10 minutes): in pairs, find the resin code on each item and match it to the key. Discuss: which codes does your local council actually collect? (Have the local list ready.) Establish that codes 1 and 2 are widely recycled, 5 increasingly, and 3, 6 and 7 rarely. Ask why mixed materials (a crisp packet) cannot go through a bottle-recycling process.
• Part 2, data carousel (15 minutes): five stations, one data card each, three minutes per station. At each, the group answers on their sheet: (a) What does this number tell us? (b) What does it NOT tell us? (c) What is one question you would want to ask the scientists? Circulate and press on the difference between "recycled" (actually made into something new) and "collected for recycling".
• Part 3, build the argument (5 minutes): whole class. On the board, collect reasons the rate is low: too many plastic types; mixed materials; contamination; cheaper to make new plastic; no collection for 1.2 billion people; recycled plastic is often lower quality ("downcycled"). Then ask the MS-ESS3-4 question: "As population and consumption per person rise, what happens to the total even if recycling improves?" (Draw the two lines: production nearly tripling versus recycling reaching only 17% by 2060 in the OECD baseline: oecd.org/en/about/news/press-releases/2022/06/global-plastic-waste-set-to-almost-triple-by-2060.html)
• Part 4, design a monitoring method (10 minutes): in groups, complete the planning sheet to design a fair way to measure plastic waste in one part of the school (canteen bins, one corridor, one year group's lunches) over two weeks. Criteria: it must produce a number that can be compared before and after a change. Constraint: no more than 15 minutes of counting a day and no handling of unclean waste without gloves. Groups swap sheets and give one improvement.

Plenary (12 minutes)

• Two groups present their monitoring method; the class chooses one to actually run (link to the Classroom Plastic Audit tool on this site, which does the calculations).
• Return to the big question. Take one sentence from three pupils.
• Exit ticket: (1) Name two reasons plastic recycling rates are low. (2) Give one number with its source. (3) Finish this sentence: "Recycling matters, but the bigger lever is ___ because ___."

Assessment

• Carousel sheet: quality of the "what it does NOT tell us" answers (source evaluation).
• Monitoring-method sheet: is it measurable, repeatable and safe? (NGSS MS-ESS3-3.)
• Exit ticket: a correct number with a named source meets the objective.

Differentiation

• Support: give a partially completed carousel sheet with sentence starters; reduce to three stations (A, B, D).
• Challenge: ask pupils to calculate the difference between "9% of 353 million tonnes" and "17% of 1,014 million tonnes" (the OECD 2060 projection) and explain why a higher percentage can still mean more waste; ask them to critique whether data card A and data card B are measuring the same thing.
• English as an additional language (EAL): glossary card with polymer, resin, landfill, incineration, mismanaged, per capita.

Homework

• Take the resin code key home. Find five items in the kitchen, record the code, and check whether your local council collects it. Bring back the list.

Safety

• Use only clean, dry packaging. Wash hands after handling. No cutting of PVC or polystyrene (dust and edges). The lump of coal, if real, goes in a sealed bag.