TOPIC: PLANTS – WEEDS
A: TEACHING AND LEARNING MATERIALS
- Samples or pictures of weeds.
- Hoe.
- Hand gloves.
- Crop and weed picture cards.
- Pupils’ writing books and pencils.
B: REFERENCE MATERIALS
- Scheme of work.
- Recommended Basic Science textbook for Primary 4.
- Online educational resources.
C: PREVIOUS KNOWLEDGE
The pupils have learnt how to prepare soil, plant seeds and care for growing plants.
D: PERFORMANCE OBJECTIVES
By the end of the lesson, pupils should be able to:
- Explain weeds.
- Identify common weeds.
- Mention places where weeds grow.
- State harmful effects of weeds.
- Mention useful effects of some weeds.
- State simple methods of weed control.
E: CONTENT
Meaning of Weeds
Weeds are unwanted plants growing where they are not needed. They may grow:
- on farms
- in gardens
- along roads
- around buildings
Examples of Common Weeds
Examples include:
- spear grass
- goat weed
- stubborn grass
Harmful Effects of Weeds
Weeds:
- Compete with crops for water.
- Compete for nutrients.
- Compete for sunlight.
- May hide pests.
- Can reduce crop yield.
Useful Effects of Some Weeds
Some weeds may:
- protect soil from erosion
- provide food for animals
- be used as medicine
- add organic matter to soil
Weed Control
Weed control means reducing or removing unwanted plants. Methods include:
Cultural method
- hand pulling
- hoeing
- mulching
Biological method
- using living organisms to control weeds
Chemical method
- using approved herbicides
Chemicals should only be used carefully and under adult supervision.
F: LESSON PRESENTATION
F1: Teachers’ Activities
- Explains the meaning of weeds.
- Shows examples of weeds.
- Discusses where weeds grow.
- Explains harmful effects.
- Mentions useful effects.
- Demonstrates hand weeding.
- Explains safe weed control.
F2: Pupils’ Activities
- Identify weeds.
- Mention places where weeds grow.
- State harmful effects.
- Mention useful effects.
- Observe hand weeding.
- Identify safe methods of weed control.
- Answer oral questions.
G: CONCLUSION
The teacher revises the meaning, effects and control of weeds. The teacher encourages pupils to keep gardens and surroundings free from harmful weeds.
H: EVALUATION GUIDE
Pupils should be able to answer the following questions:
- What is a weed?
- Mention two common weeds.
- Mention two places where weeds grow.
- State three harmful effects of weeds.
- Mention one useful effect of weeds.
- What is weed control?
- Mention two methods of controlling weeds.
- Should children handle herbicides without adult supervision?