Lesson Plan #2: Our world is made of chemicals

Learning objective

The pupils will learn that chemicals are everywhere. Some are naturally occurring. Some are man-made. The pupils will be able to recognize the hazard pictograms. They will know that the pictograms can be found on ordinary household products and that products with the pictograms on them should be handled according to the safety instructions.

Grade

4th to 6th grade (approximately 10-12 years old)

Duration

Two lessons or 90 minutes

Materials

Household chemicals with different kinds of hazard pictograms on the label, e.g. toilet cleaner, grill lighter fluid and lime scale remover. Also bring a product with the Nordic Swan and the EU-flower.

Lesson

Brainstorm: What are chemicals?

  • Start by writing the word CHEMICAL on the centre of the whiteboard.
  • Ask your pupils (in pairs) to discuss and write down what they come to think of when they see the word on the board. Give them 5 minutes to do so.
  • Write their suggestions on the board in a mind map structure around the word CHEMICAL.
  • Discuss the mind map in the class and get to the conclusion that chemicals are everywhere.

Making presumptions about the hazard pictograms

  • Display the household products on a table with the hazard pictograms hidden from the pupils.
  • Question 1: What do the displayed products have in common?
    The pupils’ answers could be: They are household products. They can be bought in supermarkets. They contain different kinds of chemicals. They should be handled with care. They have one or more hazard pictograms on the label. Write the answers on the board.
  • Flip the products and reveal the labels with the hazard pictograms. If the hazard pictogram is placed on the front of the product you can cover it up with a post-it.
  • Question 2: Why do you think that these products are labelled with hazard pictograms?
    The pupils’ answers could be: The products are toxic, they can explode, they can kill fish and so on. Write the answers on the board.
  • Explain that the hazard pictograms apply to “everyday chemicals” like household products and not e.g. cosmetics, medicine and food.

Introducing the hazard pictograms

  • Launch hannashouse.com on the projector and click the button “The pictograms”. Give a short introduction to the hazard pictograms and refer to the pupils’ answers in the previous session.
  • Ask the pupils (in pairs or small groups) to focus on just one of the 9 pictograms and read the “fold-out” text on the website. Make sure that all of the 9 pictograms are in play.
  • Presentation: The pupils tell the rest of the class about their pictogram:
    • What does the pictogram tell us?
    • On what kind of products do we usually find the pictogram?
    • What kinds of precautions are necessary to handle products labelled with this pictogram?

Reflection: Read the article “Our world is made of chemicals”

  • Ask the pupils to read the article “Our world is made of chemicals” on the website hannashouse.com. You can also print hand-outs of the article. The pupils should be able to read the article in 10-15 minutes. Do it in class or as homework.
  • Let the pupils ask clarifying questions about the article in class.
  • Discuss the subjects: “Naturally occurring chemicals and man-made chemicals”, “The dose makes the poison” and “Everything is chemistry” – think of examples of “good chemicals” and “bad chemicals” from a health or environmental perspective.

Testing presumptions: Visit Hanna’s House

  • Let the pupils (in pairs) walk through the situations in Hanna’s House on the computer or tablet.
  • Reflection in class: Discuss the 9 situations (or just some of them) and why it is important to follow the instructions on the label on the products: What could accidently happen if:
    • The dad and the aunt didn’t wear gloves cleaning the toilet and the drain?
    • The mum didn’t hide the bottle of grill lighter fluid?
    • The sister was waterproofing her shoes inside the house?
    • And so on
  • Tell the pupils that it is actually possible to reduce the use of hazardous chemicals in household products by using less harmful alternatives for example products labelled with the EU-flower or the Nordic swan. They may be less hazardous.

Try the quiz

  • Close this lesson down by letting the pupils do the hazard pictogram test on the website. How did they do?

Extend the lesson plan: The hidden hazards in your own home

  • Ask your pupils to find out how many hazard-labelled products there are in their own home or in the school building.
  • Ensure that they ask an adult to help them with this task, just to avoid accidents. They can either make a list or take pictures of the products.
  • In class you can present their findings by drawing up a simple table on the board. Observations might include:
    • What hazard pictogram did we find the most of?
    • What hazard pictogram did we find the fewest of?
    • Rate the pictograms from 1- 9 (1 = most, 9 = fewest).
    • Make a hit list and put it on the wall.
  • Alternatively you can take the class to the nearest supermarket and let them do their research here. It might be a good idea to make an appointment beforehand with the manager.