Grade by Grade
D. Structures and Mechanisms · Materials, Objects, and Everyday Structures

Less Waste: Reduce, Reuse, Recycle

D1.1 D1.2 A2.1 A3.1About 35 minutes
Learning goals
  • I can name kinds of waste that people make, like food scraps, paper, plastic and metal.
  • I can explain reduce, reuse and recycle.
  • I can make a plan to make less waste at home or at school and say why it matters.
  • I can write clear step-by-step instructions to sort waste.

Words to know

waste
Things people throw away because they think they don't need them anymore.
reduce
To use less, so there is less waste.
reuse
To use something again, maybe in a new way.
recycle
To send used materials away to be made into new things.
compost
Food scraps and plant waste that break down into rich soil.
landfill
A big place where garbage is buried in the ground.

Where does the garbage go?

Every week, families put out garbage bags. Where do they go?

Most garbage goes to a landfill. A landfill is a huge hole where garbage is piled and buried. It takes up lots of land. Some things in it, like plastic, take a very, very long time to break down.

The good news: you can help make less waste!

Kinds of waste

People throw away many kinds of waste:

  • Food scraps: banana peels, apple cores, egg shells
  • Paper and cardboard: boxes, newspaper, drawings
  • Plastic: bottles, bags, wrappers, containers
  • Metal: cans, foil
  • Glass: jars, bottles

In many Ontario communities, recycling goes in a blue box or bin, food scraps go in a green bin or a compost pile, and the rest is garbage. The rules are a little different in each town, so check yours.

A blue recycling bin with bottles and cardboard, a green bin and a black garbage bin at the curb.
Many Ontario towns use a blue bin for recycling, a green bin for food scraps and another bin for garbage. AI-generated image
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Kinds of waste: a banana peel (food), a box (cardboard), a can (metal), a bottle (plastic) and a jar (glass).

The 3 Rs

  1. Reduce: Use less. Take only the napkins you need. Use both sides of the paper.
  2. Reuse: Use things again. Pack lunch in a reusable container. Turn a jar into a pencil holder. Give outgrown boots to someone else.
  3. Recycle: Put paper, cans, some plastics and glass in the recycling, so the materials can be made into new things.

Reduce comes first because the best waste is the waste we never make!

Why it matters

Less waste means less land used for landfills, fewer trees cut down, and less litter that can hurt birds, fish and other animals. Many First Nations, Métis and Inuit teachings talk about respect for the land, taking only what you need, and using everything well. We can learn from this.

Worked example

Let's sort a lunch

After lunch, Ana has: a banana peel, a juice box, a plastic sandwich bag, and an empty yogurt cup. How could she make less waste?

  1. Banana peel: food scrap → green bin or compost.
  2. Yogurt cup: many towns accept it in the blue box. Rinse it first.
  3. Juice box: many Ontario towns recycle juice boxes, but check your town. Next time, reduce: use a refillable water bottle.
  4. Plastic sandwich bag: next time, reuse: pack the sandwich in a reusable container.
  5. Plan: Bring a reusable bottle and container tomorrow.

Ana can compost the peel, recycle the cup, and reduce and reuse with a water bottle and container. Her lunch makes almost no garbage!

Clear instructions: a sorting code

Computers and robots follow instructions exactly. Coders write instructions that are clear and in the right order. Here is a set of instructions for sorting waste. Read it with a grown-up and follow it step by step.

1. Pick up one piece of waste.
2. IF it is food, THEN put it in the green bin.
3. IF it is clean paper, cardboard, a can, a glass jar or a rinsed plastic container, THEN put it in the blue box.
4. IF it is none of these, THEN put it in the garbage.
5. IF there is more waste, THEN go back to step 1.
6. Stop. Wash your hands.

A sorting program. Each step is clear, and steps 2, 3 and 4 use IF ... THEN to make a choice.

Pick up one pieceIs it food?yesgreen binnopaper, cardboard,can, glass jar orrinsed plastic?yesblue boxnogarbageThen: more waste? Go back to the top!
The sorting code as a flowchart. Each diamond asks one IF question. Follow the "yes" or "no" arrow to find the right bin.
Worked example

Let's test our sorting code

Follow the code for an apple core.

  1. Step 1: Pick up the apple core.
  2. Step 2: Is it food? Yes. Put it in the green bin.
  3. Step 5: Is there more waste? Say no.
  4. Step 6: Stop and wash your hands.

The code sent the apple core to the green bin. The instructions worked!

Just for fun

Why was the banana peel so happy in the green bin?

Because it gets a second chance: compost turns food scraps into rich soil for new plants!

Hands-on activity

Our family waste plan

You need: paper, a pencil, and a grown-up.

  1. Look: After one meal, look at what your family throws away. Draw each piece of waste.
  2. Sort: Is it food, paper, plastic, metal or glass? Which bin does it go in?
  3. Plan: Pick one action to make less waste this week. Ideas: use a cloth napkin, bring a reusable water bottle, use both sides of paper, reuse a jar, turn off the tap... (that one saves water!).
  4. Do it every day for a week. Put a check mark each day you remember.
  5. Share: Tell someone why your action is important.

Safety: Wear gloves or let a grown-up handle anything sharp, like an opened can.

Your turn

1

Name two kinds of waste.

2

Where does most garbage go?

3

What does reduce mean?

4

You use an old jar to hold crayons. Is that reduce, reuse or recycle?

5

Where can a banana peel go instead of the garbage?

6

Give one reason making less waste is important.

7

In the sorting code, where does an empty, rinsed soup can go?

More practice: warm-up

1

What are the 3 Rs?

2

What colour bin is used for recycling in many Ontario towns?

3

Is an apple core food waste?

4

Is a newspaper paper waste?

5

Name something you can reuse.

More practice: on your own

1

Which R comes first, and why?

2

Your T-shirt is too small. Name a way to keep it out of the landfill.

3

Why should we rinse a yogurt cup before recycling it?

4

What is one way to reduce paper waste at school?

5

Follow the sorting code for a candy wrapper. Where does it go?

Challenge

1

A plastic water bottle and a metal water bottle both hold water. Which one makes less waste? Explain.

2

Make a 3-step plan to make less waste at a birthday party.

3

Fix the bug! Leo's code says: "1. Put the waste in the blue box. 2. Pick up one piece of waste." What is wrong?

Check your understanding

Quiz

1.

What does reuse mean?

2.

Where can food scraps go in many Ontario towns?

3.

Which is a way to reduce waste?

4.

Where does most garbage go?

5.

Why is making less waste important?

6.

In a set of instructions, why does the order of steps matter?

For parents and teachers

Big idea: People make different kinds of waste. We can reduce, reuse and recycle, and children can plan and carry out a real action to make less waste (D1.1). Thinking about what happens to objects when they are no longer needed connects to D1.2.

How to help: Do the family waste plan together and keep it short (one action, one week). Let your child be the "sorting boss" for a meal. Check your municipality's blue box and green bin rules; they differ across Ontario.

Coding connection: The sorting code introduces sequences (steps in order) and IF ... THEN choices (A2.1). Have your child follow it like a robot, then write their own instructions for something simple, like making toast. Look for clear steps in a sensible order.

Common difficulties:

  • Thinking recycling is always best. Remind them reduce and reuse come first.
  • Mixing up reuse and recycle. Reuse: you use it again. Recycle: it is sent away to be made into something new.

Safety: Children should not handle broken glass or sharp can lids.