30-day Swap Challenge: day-by-day tracker

How it works

• One swap per week for four weeks, plus a wild-card swap you choose. Tick each day you managed it. If you miss a day, do not restart; just tick the next one. At the end you get a number: items and grams of plastic avoided, using the weights below.
• Family, class and whole-school versions use the same list. Classes can add up their totals with a class code (no names).
• Made and funded by No Plastic Today. Licence: CC BY 4.0. Grams per item come from the European Commission's single-use plastics study, 2018, Table A2.1 (ec.europa.eu/environment/pdf/waste/Study_sups.pdf) and the UK Environment Agency carrier-bag life-cycle assessment (LCA), 2011 (biodeg.org/wp-content/uploads/2021/04/uk-ea-publishes-lca-of-supermarket-carrier-bags-.pdf). Items marked "estimate" are ours.

Why bother

• Around the world only about 9% of plastic waste was recycled in 2019 (Organisation for Economic Co-operation and Development (OECD): oecd.org/en/about/news/press-releases/2022/06/global-plastic-waste-set-to-almost-triple-by-2060.html), so the plastic you never use is the plastic you can be surest about. The United Nations estimates reuse could deliver a 30% cut in plastic pollution by 2040, the biggest single lever (UN Environment Programme (UNEP), Turning off the Tap, 2023: unep.org/resources/turning-off-tap-end-plastic-pollution-create-circular-economy). This challenge is the reuse lever, in a month.

Week 1 — Bottle to refillable (10 g per bottle avoided)

• Day 1: Find or buy one refill bottle per person. Wash it. Put it by the door. Tick: bottle ready.
• Day 2: Take it to school or work. Refill at a tap or fountain. Tick: no bought bottle today.
• Day 3: Same again. Note where the nearest refill points are (school office, water fountain, cafe that refills).
• Day 4: Cold-tap test: keep a jug in the fridge overnight and compare the taste. Tick: no bought bottle.
• Day 5: Count how many bought bottles the household would normally have used this week. Write it down.
• Day 6: Weekend outing: bottle goes in the bag before you leave. Tick.
• Day 7: Weekly check: "Did it stick?" Yes / mostly / no. What made it hard? Total bottles avoided x 10 g = grams saved.

Week 2 — Bag to reusable (8.12 g per single-use bag avoided)

• Day 8: Gather every reusable bag in the house. Put two in the car or bike pannier, one in each coat pocket or school bag.
• Day 9: First shop with your own bags. Tick: zero new bags.
• Day 10: Small shop? Carry it or use a pocket bag. Tick.
• Day 11: Start the "new-bag jar": 10p (or your coin) for every new bag taken. Tick.
• Day 12: Reminder trick: hang a bag on the front-door handle the night before a shop.
• Day 13: Weekend big shop with bags. Count bags avoided.
• Day 14: Weekly check: "Did it stick?" Remember: a bag for life needs 4 uses and a cotton bag 131 uses to have a smaller climate impact than a thin bag (growing and making cotton has a big climate cost), so the win is reuse, not buying more bags (UK Environment Agency 2011, above). Bags avoided x 8.12 g = grams saved.

Week 3 — Snack packets to bulk and tins (5.43 g per packet avoided)

• Day 15: Choose the one snack the household eats most. Buy it in a large pack or loose.
• Day 16: Decant into small tubs or a tin for lunchboxes. Tick: packet-free snack.
• Day 17: Try one snack that comes with no plastic at all (fruit, a home-made flapjack, popcorn from kernels).
• Day 18: Lunchbox check: how many packets went in today? Aim for zero.
• Day 19: Cost check: compare price per 100 g of the big pack versus the small packets. Write it down; it is usually cheaper.
• Day 20: Weekend baking or popcorn: make next week's snack.
• Day 21: Weekly check: "Did it stick?" Packets avoided x 5.43 g = grams saved.

Week 4 — Cup to keep-cup (14 g per cup and lid avoided)

• Day 22: Find a reusable cup (or a jam jar with a lid works). Put it in the bag.
• Day 23: Ask your usual cafe if they fill your own cup; most do, and some give a discount. Tick.
• Day 24: Hot chocolate at home in a real mug counts. Tick: no disposable cup.
• Day 25: School canteen or club: take your own cup. If they refuse, note why; that is useful for the letter template on this site.
• Day 26: Straws and stirrers: say "no straw, thanks" today (0.4 g each; small, but it becomes a habit).
• Day 27: Weekend cafe trip with cups for everyone.
• Day 28: Weekly check: "Did it stick?" Cups avoided x 14 g = grams saved.

Wild-card swap (Days 1–30, choose one and tick daily)

• Cling film to boxes or wax wraps (about 2 g per wrapped item, estimate).
• Wet wipes to cloths at home (1.1 g per wipe).
• Liquid soap in plastic to bar soap (about 25 g per bottle avoided, estimate).
• Plastic toothbrush to bamboo at the next change (18 g).
• Produce bags to none or a mesh bag (about 2 g per bag, estimate).
• Say no to a free plastic giveaway or party-bag toy (5–20 g, estimate).

Days 29 and 30 — Add it up

• Day 29: Total each week's grams. Add the wild-card. Divide by 1,000 for kilograms. Multiply by 12 for what a year would look like if it all stuck.
• Day 30: Choose the two swaps that stuck best and write them on the fridge as "how we do things now". Print your certificate (the on-screen version makes one) and, if you are a class, add your total to the School Pledge Board. Then pick one swap from the next list and keep going. This also counts as evidence for the "eliminate three items" target of Surfers Against Sewage Plastic Free Schools and the "act" step of Plastic Clever Schools.

Honest notes

• Missed days are normal. Just start again the next day; that matters more than a perfect streak.
• Do not buy new reusables you do not need; the best reusable is the one already in the cupboard.
• If a swap costs more or is not available where you live, skip it and choose a wild-card instead. The challenge is about what you can change, not about guilt.