Grade by Grade
C. Matter and Energy · Properties of and Changes in Matter

How Products Are Made: Manufacturing and Its Impacts

C1.1 A2.2 A3.1 A1.1About 45 minutes
Learning goals
  • I can describe the main steps in manufacturing a common product.
  • I can find physical and chemical changes in manufacturing processes.
  • I can assess positive and negative impacts of manufacturing on people and the environment.
  • I can describe how coded machines and robots are used in factories.

Words to know

manufacture
To make products, usually in large amounts in a factory, from raw materials.
raw material
A natural material before it is made into something, like trees, sand, cotton, oil or metal ore.
process
A series of steps used to make or change something.
impact
An effect, good or bad.
pollution
Harmful substances added to air, water or land.
robot
A machine that follows coded instructions to do a job by itself.

Where did your T-shirt come from?

Check the label on your T-shirt. It might say 100% cotton and Made in another country. Before it was a T-shirt, it was a fluffy cotton plant growing in a field. Lots of steps and lots of changes in matter turned that plant into your shirt. This is called manufacturing.

Cotton plants in a farm field with open brown pods full of fluffy white cotton.
This fluffy cotton is a raw material. After it is picked, cleaned, spun into thread and woven, it can become fabric for a T-shirt. AI-generated image

The steps of manufacturing

Most products go through steps like these:

  1. Getting raw materials: growing (cotton), cutting trees (wood), mining (metal ore), or drilling (oil and natural gas).
  2. Processing: changing the raw materials, often by melting, mixing, heating or chemical changes.
  3. Shaping: cutting, moulding, pressing, spinning or weaving.
  4. Putting together (assembling) the parts.
  5. Packaging and shipping the product to stores and homes.

Every step uses energy, and many steps use water.

raw materialscotton plantsprocessingspun into threadshapingknitted, dyed, cutassemblingsewn togetherpackagingand shippingto stores and youExample: a cotton T-shirt. Every step uses energy, and many use water.
The five steps of manufacturing, with a cotton T-shirt as the example under each step.
ProductRaw materialSome processesKind of change
papertrees (wood)wood is chipped and broken down into a wet pulp of fibres, then pressed and dried into sheetsmostly physical (some chemicals may be used to break down the wood)
glass jarsand and other mineralsmelted at a very high temperature, shaped, cooledmelting and cooling, plus chemical changes in the furnace
plastic bottleoil or natural gasmade into plastic in a chemical plant; plastic pellets melted and blown into a mouldchemical (making plastic), then physical (melting, moulding)
breadwheat flour, water, yeastmixed, rises, bakedmixing is physical; rising and baking are chemical
cotton T-shirtcotton plantsspun into thread, knitted, dyed, cut and sewnmostly physical; dyeing can involve chemical changes
How some common products are made.
1. mixPHYSICAL2. dough risesCHEMICAL (yeast makes gas)3. bakeCHEMICAL (can't un-bake)
Making bread uses both kinds of change: mixing is physical; rising (yeast makes gas) and baking are chemical.

Robots and code in factories

Many factories use computer-controlled machines and robots. They follow code: step-by-step instructions written by people. Ontario has many car factories, and robots there do jobs like welding and painting car parts.

  • Good impacts: robots can do dangerous, repetitive or very precise jobs. They can work quickly without getting tired.
  • Challenges: some jobs that people used to do are now done by robots. New jobs appear too, for people who design, code, fix and run the machines.

Assessing impacts

To assess means to think carefully about the good and the bad, from different points of view, and then make a judgment.

Possible impacts on society (people):

  • ✔ useful products, often at lower prices
  • ✔ jobs for workers in factories, farms, mines, trucking and stores
  • ✘ some jobs can be unsafe or tiring if workers aren't protected
  • ✘ noise, traffic and smells near factories

Possible impacts on the environment:

  • ✘ getting raw materials can destroy habitats (cutting forests, mining)
  • ✘ factories use lots of energy; burning fuels for energy causes air pollution and adds greenhouse gases that change the climate
  • ✘ some processes use lots of water and can pollute rivers and lakes if waste water isn't cleaned
  • ✘ waste and packaging end up in landfills
  • ✔ better processes, like using recycled materials, cleaning waste water, and using cleaner energy, can reduce these impacts
Worked example

Let's assess the manufacture of a cotton T-shirt

Follow a cotton T-shirt from field to closet. What are the impacts on people and the environment?

  1. Growing cotton: farms provide jobs ✔. Cotton plants need lots of water ✘, and some farms spray chemicals on crops that can wash into rivers ✘.
  2. Spinning and knitting: physical changes; factories provide jobs ✔ and use energy ✘.
  3. Dyeing: coloured dyes are added. If the waste water isn't cleaned, dyes can pollute rivers ✘.
  4. Cutting and sewing: many workers have jobs ✔. In some places, workers are paid very little or work in unsafe conditions ✘.
  5. Shipping: trucks, trains and ships burn fuel ✘.
  6. Judgment: T-shirts are useful and give people jobs, but making them uses lots of water and energy. Wearing shirts longer, buying used and choosing companies that clean their waste water can reduce the harm.

A strong assessment lists good and bad impacts on people and the environment, then makes a judgment with reasons.

Just for fun

Why did the factory robot take a vacation?

It needed to recharge its batteries! (Real factory robots do work for hours without a break, but they still need people to fix and program them.)

Hands-on activity

Product detective

You need: 3 products from home (for example a T-shirt, a glass jar, a cereal box), paper and pencil, and a grown-up to help you search online or in library books.

  1. For each product, read the label or package. What is it made of? Where was it made?
  2. Research (with a grown-up): find the raw materials and the main steps used to make it.
  3. Draw a flowchart for one product: raw material → processing → shaping → packaging → shipping → you.
  4. Mark each step P (physical change) or C (chemical change) if you can tell.
  5. Make a two-column chart: Impacts on people and Impacts on the environment. List at least two good and two bad impacts.
  6. Write your judgment: "I think making this product is... because...".
  7. Bonus: find out if any of your products were made with help from robots or computer-controlled machines.

What to look for: a flowchart with at least 4 steps, impacts on both people and the environment, and a judgment with reasons.

Safety: a grown-up helps with online searches. Handle glass jars carefully.

Your turn

1

What does manufacture mean?

2

Name the raw material for each: paper, glass, plastic.

3

List the five main steps of manufacturing.

4

Give one positive impact of manufacturing on people.

5

Give one negative impact of manufacturing on the environment.

6

How do robots in factories know what to do?

More practice: warm-up

1

Is melting plastic pellets a physical or chemical change?

2

Is baking bread in a factory a physical or chemical change?

3

Is cutting fabric for a shirt physical or chemical?

4

Name a job robots do in Ontario car factories.

5

What is a raw material?

More practice: on your own

1

Why do factories often cause air pollution?

2

Give one good and one bad impact of using robots in factories.

3

How can dyeing T-shirts harm a river? How can it be fixed?

4

Making plastic bottles involves a chemical change and a physical change. Name each.

5

Why does a good assessment look at more than one point of view?

Challenge

1

A paper company starts using recycled paper instead of new trees for some of its products. Assess this change.

2

Why might a product made close to home have a smaller impact on the environment than the same product shipped from far away?

3

Write a few lines of code a factory robot might follow to put caps on bottles.

Check your understanding

Quiz

1.

The raw material for paper is...

2.

Which step comes first in manufacturing?

3.

Melting plastic pellets and moulding them into a bottle is a...

4.

Which is a positive impact of manufacturing on society?

5.

Factory robots do their jobs by following...

6.

To assess impacts means to...

For parents and teachers

Big idea: Ontario Grade 5 expectation C1.1 asks children to assess the impacts on society and the environment of various processes used in the manufacture of common products. The lesson connects to coding and technology in everyday life (A2.2), practical applications (A3.1) and research (A1.1).

How to help: Read product labels together. Help your child search for "how is paper made" or watch a factory tour video together. Ask: "Who benefits? Who might be harmed? What about the environment?"

Common difficulties:

  • Listing only bad impacts or only good ones. Assessments need both.
  • Forgetting transportation and packaging as parts of manufacturing.
  • Thinking robots "think for themselves". They follow code people write.

Avoid making any one country or company the "bad guy"; focus on processes and choices.