1 - Getting Started ~5 mins
Your teacher is holding a tray of clean classroom waste. Look carefully at each thing. Where should it go when we are finished with it?
Hands up: which of these do you think could be used again somehow?
Hold up one class tray of clean sample waste (or one surprising pair, such as a clean plastic bottle beside a crisp packet). Keep the hook light: one curiosity question, no full sort yet. There is nothing on the board to look at yet; the physical tray is the focus.
Key question: If everything we throw away had to stay in our classroom forever, what would we want to change?
Surface quick prior ideas only (bins at home, the green bin, compost). Do not teach the four groups yet.
Ready for the next step: for each group, have four destination labels ready (Recycle, Compost, Reuse, Landfill) with either four shallow trays/hoops or four newspaper mats / floor spaces. That is four labelled destinations per group, not one class set of four trays only.
2 - Four Places for Waste ~8 mins
Look at the clean bottle your teacher is holding. Recycle means turn a used material into something new. A clean plastic bottle can often be recycled.
Now look at the crisp packet. Landfill is where rubbish goes when we cannot recycle, compost or reuse it. Many crisp packets still end up there.
Hands up: which place is better for a clean plastic bottle, recycle or landfill? Which place is worst for the environment if we send everything there?
In Ireland, shops charge for plastic bags so people bring bags they can use again. That is reduce and reuse in real life.
Now look at a dry leaf or fruit peel. Plant scraps can go to compost, where they break down into compost that feeds soil.
Look at a clean jar or the blank side of scrap paper. That can be reuse: use it again as it is.
Call out: dry leaf — compost or landfill? Clean jar — reuse or landfill?
Teach the destinations with real items in hand before pupils sort. Project only the short board text in chunks as you hold each item. Pupils stay seated and watch; they do not hold items yet. Pause for the call-out after the recycle/landfill pair, then again after compost/reuse, so the four places do not blur together. Use the table below yourself.
Order that lands for 3rd class: start with the core pair recycle (clean bottle) and landfill (crisp packet), then the Ireland bag-charge line, then add compost with the dry leaf or sealed peel sample, and reuse with the jar or scrap paper. Do not read all four definitions as one unbroken block.
| Concept | Why it matters | Example |
|---|---|---|
| Recycle — turning a used material into something new so it does not have to be thrown away | Recycling means fewer brand-new materials need to be made from scratch | Clean paper, cardboard, plastic bottles, cans and glass jars often go in the recycling bin at school or home |
| Compost — letting plant and food scraps break down into compost that feeds soil and helps plants grow | Compost feeds gardens and keeps wet food waste out of landfill | Fruit peels, tea leaves and dry garden leaves can go in a compost caddy or brown bin |
| Reuse — using something again for the same job or a new job | Reuse needs no factory step first, so it often saves the most | A clean jar for pencils; the blank side of a worksheet for rough work |
| Landfill — a place where rubbish that cannot be recycled, composted or reused is buried | Landfill takes up land and can harm the environment, so we try to send as little there as we can | Many crisp packets and mixed dirty items still end up as landfill waste |
| Reduce — using less in the first place so there is less waste to sort | Less waste means less sorting and less that ends up buried | A scrap-paper tray so the class uses fewer new sheets |
Nature of STEM weave: Ireland introduced a plastic-bag charge in shops so people would bring reusable bags instead. Sorting waste into different bins is now part of everyday Irish life at home and school. The pupil-facing bag-charge line sits after the crisp-packet beat; you can extend with: What did people do with packaging before recycling bins were common?
Misconception to head off: Pupils often say “all plastic recycles.” Dirty, mixed or filmy plastics (many crisp packets, some wrappers) often cannot go in the ordinary recycling bin. Clean and dry matters.
Modelled sort (think aloud once before groups start): Pick up the clean plastic bottle. I wonder where this should go. I predict recycle, because the bottle is one clean material and can be made into something new. I check: can I reuse it as it is? Maybe as a water bottle, but today it is empty sample waste. Is it plant scrap? No. Can the material be recycled? Yes, clean plastic bottle. I place it in Recycle. I think clean bottles belong in recycle so they are not buried in landfill.
3 - Audit and Sort the Classroom Waste ~16 mins
In your group, look carefully at each clean waste item on your tray. Talk about what it is made of. Then place it in one of the four places: recycle, compost, reuse or landfill.
If your group disagrees, say why. Be ready to explain one choice to the class.
Before the lesson
- Gather only clean, dry, safe sample waste (no food goo, no sharp metal, no bathroom waste).
- Print the four sorting labels (Recycle · Compost · Reuse · Landfill) for each group.
- Destination kit (choose one realistic option per group): four shallow trays or hoops with a label on each, or four labelled newspaper mats / floor spaces, or four hoops on the floor. The newspaper-mat option needs no extra trays and is fine for a busy classroom.
- Put gloves out; remind pupils to wash hands after the sort.
Suggested clean items (about 8–10 per group tray)
- Scrap paper or a used worksheet
- Newspaper strip
- Small piece of cardboard
- Empty rinsed plastic bottle
- Clean yogurt pot
- Clean aluminium can (edges safe) or foil ball
- Clean glass jar only if you are happy supervising glass; otherwise a clean plastic jar
- Crisp packet
- Polystyrene packing piece or plastic film wrapper
- Fabric scrap or clean jam-jar lid (good reuse talk)
- Dry leaf or dry tea leaves in a small paper cup (compost)
- Clean dry fruit peel sample in a sealed clear bag if you want a compost example without mess
During the activity
Groups of about four work at one waste tray and four labelled destinations. Circulate and ask: What is it made of? Could someone use it again as it is? Would dirt stop it being recycled?
Look-fors: pupils touching and naming the material; groups changing their minds with a reason; at least one item that sparks debate (crisp packet, polystyrene, fabric).
Differentiation: less confident groups get a smaller tray (6 items) and sentence starter cards said aloud — We put this in … because …. Confident groups add a second sort: which recycled items are paper-based and which are metal or plastic.
Safety: gloves on for the sort; no tasting; glass only with close supervision; wipe any spills; wash hands when the tray is cleared.
4 - Check the Sort on the Board ~10 mins
Now we will sort the same kinds of items on the interactive activity. Watch the yes-or-no questions. Call out which group each item should go to: recycle, compost, reuse or landfill.
Did your tray group match the board, or did you change your mind?
Where should this waste go?
Open the sorting-tree interactive in explore mode on the IWB. Drive it yourself; pupils call out answers. Fold the whole class in: Do you agree with this group? What would make this item hard to recycle?
What appears on screen: item cards for newspaper, apple core, plastic bottle, crisp packet, cardboard box, banana peel, glass jar, aluminium can, scrap paper, polystyrene. Groups are recycle, compost, reuse, landfill. Yes/no questions guide the path: Can we use it again just as it is? Is it plant or food scrap? Can this clean material usually be recycled?
Expected placements (teacher key):
- Reuse: clean glass jar (as a container), scrap paper (blank side for rough work) if you choose reuse over recycle in discussion — accept recycle for paper if the class argues well; name both as thoughtful.
- Compost: apple core, banana peel
- Recycle: newspaper, plastic bottle, cardboard box, aluminium can, glass jar (if not reused)
- Landfill: crisp packet, polystyrene (in many ordinary school bins these cannot go in mixed recycling)
Local council rules differ slightly. Say so honestly: At school we follow our school bins; at home your county’s bin rules might name a few extras. Prefer the school’s real bin labels if they differ, and adjust talk to match.
Debate worth having: glass jar — reuse as a pot, or recycle? Both can be right; reuse often comes first when the jar is useful.
5 - Record the Sort and Our Idea ~10 mins
You already know four places for waste: recycle, compost, reuse and landfill. Here is one new idea for our class action only. It is not a fifth sorting tray.
Reduce means using less in the first place, for example sharing one big soap refill instead of many small bottles. Reuse means using something again, like bringing the same water bottle every day so we buy fewer single-use ones.
On your Investigation Journal page, record two or three items your group sorted and which place each went. Write one short reason for one of those choices.
Then write or draw one practical idea that would help our class reduce waste or reuse something we usually throw away.
This is the paper recording beat inside the lesson sitting (not homework). Pupils use the Investigation Journal page for this lesson. Tell them what to capture, not where boxes sit on the page.
Keep cognitive load light: the four destinations stay the core set from the sort. Reduce is only a plain “use less” bridge into the action idea — do not add extra terms or extra recording fields, and do not ask pupils to re-learn all five words while writing.
- Must do in the 10 minutes: two or three sorted items with the group each went into; one short reason for one item; one class action idea (reduce or reuse) small enough to try this month
- Extension if time: add more sorted items or a second action idea
Support writers with oral rehearsal first: We put the … in … because … Drawing plus labels is fine. No typing into the platform.
Name the page only as the Investigation Journal page. Do not say internal sheet ids aloud or in notes to pupils.
Action idea quality bar: practical and class-sized — e.g. a scrap-paper tray for rough work, a clean-jar pencil pot station, reusable water bottles reminded each Monday, a classroom compost caddy for fruit peels if the school allows it. Steer away from huge promises nobody can keep.
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