removing soluble and insoluble substances from water
acting like sponges and regulating the flow of water
Teacher Input 4
Greet the learners.
Remind them that in the previous lesson, they learnt about water pollution. Can they remember what water pollution is?
Answer: Water pollution happens when pollutants (insoluble substances, soluble substances and living germs) are released into water bodies (e.g. rivers, oceans, dams, ponds and wetlands) without enough treatment to get rid of harmful compounds. Humans (people) are the main cause of water pollution.
What are the 3 types of things that pollute our water and give examples.
Answers should include:
Insoluble pollutants, e.g. oil, plastic packets, toilet waste
Soluble pollutants: g. soap, poison
Living germs: g. bacteria in toilet waste
What can we do to keep our water systems clean?
Answers can include:
We should stop throwing plastic bags and bottles into our rivers, dams and oceans.
We should make sure that our human waste (sewerage) is disposed of properly.
We should stop using fertilizers and insecticides that are poisonous chemicals(rather use eco-friendly products)
Tell the learners that humans are mostly the cause of pollution, e.g. ships that leak oil; businesses and factories that dump waste into rivers (mining and chemical factories).
Nature has its own way of cleaning polluted water. Can they guess what this is?
Do learners know what a wetland is? Tell them that they are going to watch a 2 short videos on wetlands.
“The video shows how wetlands, as part of a system of rivers, creeks and lakes, help watersheds maintain good health. Wetlands help watersheds to improve water quality and biodiversity. They help regulate water flow which reduces flooding impacts, and also collects sediment and filters pollutants. The best way to maintain healthy watersheds is by protecting and restoring wetlands, and by reducing what goes into the water, such as excess nutrients and extra sediment.”
Tell learners that they have received a lot of information on wetlands. They can test their knowledge by completing WORKSHEET D: Facts about wetlands.
Guide learners as they undertake this activity and explain how this worksheet will be assessed.
Teacher to use WORKSHEET D: Memorandum to mark the learners’ work.
Teacher Input 5
Tell learners that they now know that wetlands are nature’s way of purifying our water. Wetlands also have other abilities.
We are going to do three simple demonstrations to see and understand the three unique abilities that wetlands have and why they are so important to nature.
Divide the class into three groups, each group being responsible to carry out a different demonstration
The following will be required:
Activity 3 (WORKSHEET E: Wetlands are like giant sponges)
half a cup of sand
a container with water
a sponge (e.g. bath- or kitchen sponge)
Activity 4 (WORKSHEET F: Wetlands slow down flood waters)
plastic two litre cooldrink bottle
a jug or bottle containing water (at least 2 litres)
an empty container, e.g. ice cream dish
Activity 5 (WORKSHEET G: Wetlands are natural filtration systems for purifying water)
a glass of water
an empty glass
a small amount of filter coffee or tea leaves
a coffee filter or piece of cloth
an elastic band
Learner Activity 5
Handout the relevant worksheets to the groups of learners.
Guide learners as they follow the instructions in WORKSHEET E / F/G in preparation for the class demonstration.
Let each group repeat the demonstration they have practiced to the rest of the class and make a presentation on –
What they did?
How this demonstration explains how wetlands work.
Instruct learners to write a short report about wetlands. The report should include the following:
A definition of wetlands.
A description of how wetlands work (using the example that they had to demonstrate to the class).
An explanation of the importance of wetlands.
An indication of the impact of the loss of wetlands for biodiversity and water quality.
Guide the learners as they undertake the writing of this report and explain how the report will be assessed.
Teacher Input 6
Term 2 (Matter and Materials), Topic 5 (Mixtures and water resources) of the Natural Sciences and Technology Grade 6A (Thunderbolt Kids) textbook contains instructions on how to build a model of a wetland.
You can also find these instructions on the Thunderbolt Kids website:
Tell your learners that they will be building a model of a wetland.
Ask learners if they can list the 3 things that make wetlands important for the environment.
they soak up and store water
they slow down flood waters
they act as filtration systems
Emphasize that wetlands also provide a habitat to many different plant and animal species. Wetlands are important because of their biodiversity.
Ask learners if they can remember what a habitat is?
Answer: Habitat is a place where species get what they need to survive: food, water, cover, and a place to raise young. In other words, a habitat is a plant or animal's home.
Ask learners if they can remember what biodiversity means?
Answer: Biodiversityis the term given to the variety of life on Earth. It is the variety within and between all species of plants, animals and micro-organisms and the ecosystems within which they live and interact.
Show PRESENTATION 3: How do wetlands help to purify water?
Explain to learners that they will now watch a video about how people use wetlands in Malawi and Zambia to help them survive. Tell them that they will be required to answer questions about the video afterwards.