Week Two
Subject: Physical And Health Education
Class: Primary Two
Week of the Third Term: 2nd Week
Topic: Methods of Purifying Water
Subtopic: Filtration and Boiling
Instructional Objectives
At the end of the lesson, pupils should be able to:
- Describe the process of filtration and its importance in purifying water.
- Explain how boiling purifies water and why it is a necessary method.
- Demonstrate both filtration and boiling methods in a simple, safe manner.
Entry Behaviour
Pupils should have basic knowledge of water sources and understand that some water may not be clean for drinking.
Instructional Materials
- Water filtration materials (sand, gravel, cotton, a plastic bottle cut in half)
- A pot for boiling water
- A heat source (stove) and safe handling instructions
- Visual aids: Posters or charts showing filtration and boiling processes
Reference Materials
Baba Gbefwi, N., Okoroigwe, E., & Akinmorin, A. (2017). Wabp Physical and Health Education for Primary Schools Book 2. Lagos: West African Book Publisher.
Adeyanju, S. A., Danladi, M. I., Edegbai, B., Igbanu, V. C., & Okunrotifa, E. B. (2022). Spectrum Physical and Health Education for Primary School 2 Textbook (BEC Edition). Lagos: Spectrum Book Limited.
Content
Methods of Purifying Water: Filtration and Boiling
Why Purify Water?
Water is essential for life, but it can sometimes contain harmful substances, germs, or dirt that can make us sick. Purifying water makes it safe to drink and use. Two common methods of purifying water are filtration and boiling.
1. Filtration
What is Filtration?
Filtration is a method of purifying water by removing impurities, dirt, and particles using a filter. A filter can be made of different materials like sand, charcoal, or special cloth.
How Does It Work?
- Step 1: Water is poured into a container with a filter.
- Step 2: As the water passes through the filter, dirt and particles are trapped, while clean water flows out.
Benefits of Filtration:
- It removes large particles and some germs from the water.
- It is a simple and quick way to make water cleaner.
Example of Filtration:
You can use a clean cloth or a coffee filter to strain water. This will help remove visible dirt and debris.
2. Boiling
What is Boiling?
Boiling is another method to purify water by heating it to a high temperature. When water boils, it reaches 100 degrees Celsius (212 degrees Fahrenheit), which kills most germs and bacteria.
How Does It Work?
- Step 1: Place the water in a pot and put it on the stove.
- Step 2: Heat the water until it bubbles and boils.
- Step 3: Let it boil for at least one minute. If you are at a higher altitude, boil for a bit longer.
Benefits of Boiling:
- It effectively kills harmful germs and bacteria that can make you sick.
- Boiling is a reliable method to ensure the water is safe to drink.
When to Use Boiling:
Boiling is especially important when you suspect the water may be contaminated or if it comes from a source that is not clean.
Lesson Presentation (Step-by-Step Procedure)
Step 1: Introduction
Engage pupils by asking, “Why do we need to make sure our water is clean?” Share a story about someone who got sick from drinking dirty water.
Step 2: Explanation
Explain the two methods of purifying water: filtration and boiling. Use simple terms and examples from their daily lives to illustrate both methods.
Step 3: Demonstration
Demonstrate the filtration process using the materials prepared. Show how to layer sand, gravel, and cotton in the bottle to filter dirty water. Then, demonstrate boiling by heating water in a pot and explaining what happens when water reaches its boiling point.
Step 4: Guided Practice
Have pupils form small groups and allow them to practice the filtration method using the materials provided. Assist them as they work through the steps.
Step 5: Independent Practice
Ask pupils to draw a picture of either the filtration or boiling process and write a few sentences explaining how it purifies water.
Step 6: Feedback
Provide feedback on their drawings and explanations, clarifying any misconceptions about the methods.
Evaluation
Formative Assessment:
Observe pupils during group work to assess their understanding of the filtration method and ensure they can identify the materials used.
Summative Assessment:
At the end of the lesson, conduct a simple quiz where pupils answer questions about the filtration and boiling methods of water purification.
Summary/Conclusion
Summarize the key points: the importance of purifying water, the filtration process, and how boiling helps in making water safe to drink. Encourage pupils to ask any final questions.
Assignment
Instruct pupils to think about how they can ensure the water they drink is clean and to write a short paragraph about one method they can use at home.