TOPIC: OBJECTS THAT SINK IN WATER
A: TEACHING AND LEARNING
MATERIALS
- Bowl of water.
- Stone.
- Metal spoon.
- Coin.
- Nail.
- Cork.
- Leaf.
- Observation chart.
- Pupils’ writing materials.
B: REFERENCE MATERIALS
- Scheme of work.
- Recommended Basic Science textbook for Primary 2.
- Online educational resources.
C: PREVIOUS KNOWLEDGE
The pupils have learnt that some objects such as dry wood, cork and
some plastic objects may float on water.
D: PERFORMANCE OBJECTIVES
By the end of the lesson, pupils should be able to:
- Explain the meaning of sinking.
- Identify objects that sink in water.
- Mention examples of sinking objects.
- Differentiate between floating and sinking.
- Carry out a simple sink-or-float activity.
- Record simple observations.
E: CONTENT
Meaning of Sinking
An object sinks when it goes down to the bottom of
water. For example: 💧 + 🪨 = a stone sinks.
Objects That Usually Sink
Examples include:
- Stone.
- Coin.
- Metal nail.
- Metal spoon.
- Some glass objects.
Floating and Sinking
Floating: The object stays on or near the water
surface. Sinking: The object goes to the bottom.
Examples: 🍃 Leaf — may float. 🪨 Stone — sinks.
Simple Experiment
Put the following objects into water one at a time:
- Stone.
- Coin.
- Leaf.
- Cork.
- Metal spoon.
Observe whether each object floats or sinks.
| Object | Observation |
|---|---|
| Leaf | Floats |
| Cork | Floats |
| Stone | Sinks |
| Coin | Sinks |
| Metal spoon | Sinks |
Important Note
Whether an object floats or sinks can depend on its material, shape
and whether it contains air.
F: LESSON PRESENTATION
F1: Teachers’ Activities
- Revises floating objects.
- Introduces the meaning of sinking.
- Drops a stone into water.
- Tests different objects.
- Guides pupils to classify objects into floating and sinking
groups. - Records the observations on the board.
- Reinforces safety rules.
F2: Pupils’ Activities
- Observe objects placed in water.
- Identify sinking objects.
- Compare floating and sinking.
- Sort objects into two groups.
- Record observations.
- Answer oral questions.
G: CONCLUSION
The teacher explains that objects that go to the bottom of water
sink, while objects that remain on or near the surface
float.
H: EVALUATION GUIDE
Pupils should be able to answer the following questions:
- What does sinking mean?
- Mention three objects that sink in water.
- Does a stone float or sink?
- Does a cork usually float or sink?
- What is the difference between floating and sinking?
- Sort these into floating and sinking objects: stone, leaf,
coin, cork.