Classroom plastic audit (ages 8–18, with a picture tally for 5–7)

What this is

• A one-week count of the single-use plastic that passes through your class, canteen or lunchboxes, turned into grams per year and a three-swap action plan.
• Works on paper (this worksheet) or on screen (the interactive version on this site does the sums, makes the chart and exports a comma-separated values (CSV)). No login, no pupil data stored.
• Ages 8–18 teacher-led; a picture-tally version for ages 5–7 is included at the end.
• Method adapted from the waste-audit lesson in US National Oceanic and Atmospheric Administration (NOAA)'s public-domain "Turning the Tide on Trash" (marinedebris.noaa.gov/curricula/turning-tide-trash), with our own weights table. Made and funded by No Plastic Today. Licence: CC BY 4.0.

Before you start (teacher, 10 minutes)

• Choose ONE scope so the numbers are comparable next time: (a) lunchboxes, (b) classroom bins, (c) the whole class for a day, or (d) the canteen for one sitting.
• Decide the count window: five school days is the minimum for a fair average.
• Print one tally sheet per day and one summary sheet. Gloves and tongs for bin audits; nothing is handled that has raw food or bodily waste on it.
• Say to the class: this is a count, not a judgement. Nobody is named. Families choose what they can afford and what the shops sell; our job is to find the easy wins.

The 12 categories (tally sheet)

• 1. Drinks bottle (any size)
• 2. Drink carton straw or pouch straw
• 3. Crisp or snack packet
• 4. Cling film (count each wrapped item as one)
• 5. Sandwich or freezer bag
• 6. Yoghurt or dessert pot (include the lid)
• 7. Fruit pot or ready-meal tray with cutlery
• 8. Cup with lid (hot or cold)
• 9. Sweet or bar wrapper
• 10. Stationery packaging (pen packs, glue-stick tubes, pencil sleeves)
• 11. Disposable cutlery (count each piece)
• 12. Other (write what it was)
• Optional columns per item: "Where did it come from?" (home / shop / school) and "Could it be swapped?" (yes / maybe / no).

Daily count (10 minutes a day, five days)

• Each group counts one category set (categories 1–4, 5–8, 9–12) so nobody handles more than a few items.
• Tally with marks in fives. Do not weigh; we use standard weights so every class is comparable.
• At the end of the day the teacher (or a data monitor) copies the totals to the summary sheet.

Weights table (grams per item)

• Drinks bottle, still, small: 10 g. Fizzy or large bottle: 18 g (small fizzy) to 45 g (1–2 litre). Sources: European Commission single-use plastics study 2018, Table A2.1 (ec.europa.eu/environment/pdf/waste/Study_sups.pdf); industry bottle-weight summaries (bottlefirst.com/what-does-a-water-bottle-weigh/).
• Straw: 0.4 g (European Commission, 2018, Table A2.1, ec.europa.eu/environment/pdf/waste/Study_sups.pdf).
• Crisp or snack packet: 5.4 g (EC 2018, as above).
• Cling film per wrapped item: 2 g (our estimate from a 30 cm x 30 cm sheet of 10-micron film; label as estimate).
• Sandwich or freezer bag: 2 g (our estimate; label as estimate).
• Yoghurt or dessert pot with lid: 5 g (our estimate; label as estimate).
• Fruit pot or tray with cutlery: 20 g for the container (EC 2018 estimate) plus 2.6 g per piece of cutlery (EC 2018, ec.europa.eu/environment/pdf/waste/Study_sups.pdf).
• Cup with lid: 11 g cup plus 3 g lid = 14 g (EC 2018, as above).
• Sweet or bar wrapper: 1 g (our estimate; label as estimate).
• Stationery packaging: 5 g (our estimate; label as estimate).
• Disposable cutlery: 2.6 g per piece (EC 2018).
• Other: 5 g unless you know better.

The sums (summary sheet)

• Step 1. Items per week = add the five daily totals for each category.
• Step 2. Grams per week = items per week x weight from the table, category by category. Add them up.
• Step 3. Grams per year = grams per week x 38 (school weeks). Divide by 1,000 for kilograms.
• Step 4. Per pupil = grams per year / number of pupils counted.
• Step 5. Top three = the three categories with the most grams (not the most items; a bottle weighs as much as 25 straws).
• Step 6. Whole school = per-pupil figure x pupils on roll. Write it as "about ___ kg a year, the same as ___ 10 g bottles".
• Step 7. Comparison line for older pupils: the average person in the United States generated about 221 kg of plastic waste in 2019, and in European Organisation for Economic Co-operation and Development (OECD) countries 114 kg (OECD Global Plastics Outlook: oecd.org/en/publications/global-plastics-outlook_de747aef-en/full-report/component-7.html). Single-use plastic waste alone was about 59 kg per person in Australia, 53 kg in the US and 44 kg in the UK (Plastic Waste Makers Index 2021, by the Minderoo Foundation, a philanthropic organisation: cdn.minderoo.org/assets/uploads/resources/plastic-waste-makers-index-2021/20211105-plastic-waste-makers-index.pdf). Your school-hours figure will be a small slice of that; say so.

Action plan (one lesson)

• For each of the top three categories, list the swap, who has to do something (pupil, family, school, canteen), the cost (usually nothing or a one-off), and the grams per year avoided if everyone swaps.
• Pick the swap with the best grams-avoided for the least effort. That is Swap 1. Pick two more.
• Write the class pledge: "This term we will ___, ___ and ___. We expect to avoid about ___ kg of plastic a year. We will count again on ___." Sign it. Post it on the School Pledge Board (on this site) if you want it public.
• These three swaps are the same shape as the "eliminate three items" target used by Surfers Against Sewage Plastic Free Schools and the "act" step of Plastic Clever Schools, so the evidence you gather here can be submitted to either award.

Count again

• Repeat the five-day count at the end of term with the same scope. Report: items per week before and after, grams per year before and after, and which swap stuck. Celebrate the number, whatever it is; a real drop of 10% that sticks beats a claimed 50% that does not.

Picture tally for ages 5–7

• Use four pictures only: bottle, crisp packet, yoghurt pot, wrapper. Children add a sticker or a mark under the picture each time they finish one. At the end of the week, count the stickers together and make a bar chart with the stickers themselves. Ask: "Which column is tallest? What could we use instead?" No weights, no multiplication.

Data and privacy

• The paper version stores nothing. The on-screen version keeps totals only in your own browser (a class code you choose, no names) so you can compare term on term, and lets you download a CSV. Nothing is sent to us unless you post a pledge.