Lesson 26

Lesson 26: Different Ways Of Waste Disposal

Learning Objective

Understanding the effects of improper disposal of waste on the environment

Syllabus Correlations

· Theme: Investigating Materials

· Learning Area: Waste Management

· Learning Objective: Understanding the effects of improper disposal of waste on the environment

Learning Outcomes:

Pupils should be able to:

· state the improper ways of waste disposal.

· state the proper ways of waste disposal.

· describe the harmful effects of improper waste disposal.

Concept(s) Introduced:

· what is the difference between improper and proper waste disposals;

· harmful effects of improper waste disposals.

Skills Covered:

· Observing, classifying, making inferences, interpreting data, making conclusions, comparing and contrasting.

Vocabulary/ New Words:

acid rain, air pollution, bad smell, decay, dispose, emit, flash flood, improper waste disposal, pollution, recycle, reuse, waste

Value(s) Incorporated:

· Having an interest in and curiosity about the environment.

· Being diligent and persevering.

· Realising that science is a means to understand nature.

· Thinking rationally

· Analysing the things around us

Materials Needed:

-

Point(s) to Note:

Explain improper and proper ways of waste disposals as well as effects of the former.

Teaching Strategies
Set Induction	Show the images of a tidy and messy room each. Ask pupils to choose which one they prefer to live in. Ask pupils to give reasons to support the choice. Teacher explains what the reason is for choosing the tidy room instead of the messy room. Component: Introduction
Step 1	Play the content component. Show the videos to differentiate between improper and proper ways to dispose waste. Ask pupils to explain how waste can be disposed of improperly. Teacher introduces the examples of improper waste disposal namely littering or dumping of rubbish, open burning of rubbish and release of chemical waste by factories. Play the content component. Teacher explains on littering or dumping of rubbish. Ask pupils what are the effects of littering. Explain that littering pollutes water. It also blocks drains and rivers that cause flash floods. Explain that rubbish is a breeding ground for pests and increase the spread of diseases. Play the content component. Teacher explains on open burning of rubbish. Ask pupils what are the effects of open burning. Ask pupils whether they have witnessed open burning before. Explain that haze causes eye irritation and breathing difficulties. Plastic materials being burned emit toxic gases dangerous to our health. Ask pupils to find out what plastic is made of. Play the content component. Teacher explains on release of chemical waste from factories. Ask pupils what are the effects of release of chemical waste. Ask pupils whether they have witnessed factories releasing chemical waste into rivers or drains before. Explain that aquatic animals and plants are killed due to water polluted by chemical waste. Ask pupils whether they have seen release of chemical waste into the air. Explain that air pollution can cause damage to our lungs and throat, especially those who are asthmatic. Play the content component. Ask pupils what the proper ways to dispose waste are. Teacher explains examples of the ways. Ask pupils how to reuse and recycle rubbish. Ask pupils what an incinerator is. Explain that it is used to burn rubbish to prevent pollution. Play the content component. Ask pupils what should be done to prevent water pollution. Explain that rubbish and untreated water waste must not enter drains and rivers. Direct pupils to discuss on how waste water must be treated. Teacher explains that water must be treated in a sewage treatment plant. Explain that waste water from factories must be treated as well. Play the content component. Ask pupils what must be done to prevent air pollution from factories. Teacher explains that the ways are to build factories away from housing area, fit tall chimneys and filter the smoke. Ask pupils what each of the ways can bring benefits and reduce air pollution. Play the content component. Ask pupils what improper disposal of waste can cause. Encourage pupils to cultivate the habit to dispose waste properly. Play the content component. Teacher highlights on air pollution. Ask pupils what is the effect of haze. Explain how the effects of eye irritation and breathing difficulties. Explain how haze also limits our vision. Play the content component. Teacher highlights on water pollution. Ask pupils what is the effect of polluted water. Explain how the chemicals kill animals and plants in water. Explain how polluted water destroys natural habitat of animals. Play the content component. Teacher highlights on disease. Ask pupils what is the types of diseases that can spread. Explain what and how animals carry microorganisms that spread diseases. Ask pupils what disease Aedes mosquitoes bring. Ask pupils to find out what are the symptoms of dengue. Encourage pupils that if the any of the symptoms prevail, they have to see a doctor and get treated. Play the content component. Teacher highlights on acid rain. Ask pupils what is acid rain. Explain how acid rain can kill plants and aquatic animals. Ask pupils whether acid rain can cause erosion. Explain that acid rain makes iron to rust and buildings to erode. Play the content component. Teacher highlights on flash floods. Ask pupils what is flash flood and whether they have encountered one before. Explain how flash floods can destroy homes and other valuable properties. Ask pupils how flash floods can affect human health. Explain that flash floods cause water contamination and also water-borne diseases. Ask pupils what the other effects of flash flood are. Explain that it can cause damage to public structures and bring about traffic jams. Play the content component. Teacher recaps what improper waste disposal can cause. Show pupils the video on improper waste disposal. Explain that such disposal causes serious damage to the environment. Component: Content
Step 2	Play the activity component. Ask pupils to drag and drop the harmful effects of improper waste disposal with the images. Tell pupils to observe the images well to complete the activity. Play the activity component. Ask pupils to click the characteristics to each improper waste disposal. Component: Activity
Step 3	There are five questions in this component covering the learning outcomes. Questions 1 to 3 are objective questions. Q4 is a drag and drop activity. Pupils drag and drop the correct answers for the questions. Q5 consists of true or false questions. Pupils need to identify whether the statements are true or false. Use evaluation sheets to assess the pupils’ understanding of this lesson. Component: Evaluation
Step 4	A case study on water from natural resources. Ask pupils what water from natural resources contains. Teacher explains the bad effects of drinking such water. Ask pupils what should be done to the water so that it is safe for drinking. Teacher introduces what water purification is. Explain the diseases which unclean water can bring like cholera and typhoid. Encourage pupils to drink clean water that is purified water. Component: Extension
Conclusion	Conclude the lesson by playing this component to further reinforce understanding of the lesson. Help pupils to differentiate between improper and proper waste disposals. Emphasise how both disposals can happen and also the effects of improper disposals. Component : Summary