Basic Science and Technology
Primary 6/ Basic 6
Previous lesson :
The pupils have previous knowledge of Our Weather
OUR EARTH AND SKY
Specific Behavioural objectives :
At the end of the lesson, the pupils should be able to
- Describe the shape of the earth
- Mention some sky elements
- explain the functions of the stars , moon , planets ,sky
- list the planets in the solar system
- Explain the force of the earth pull (Gravity)
Instructional Materials :
- Wall charts
- Related Online Video
- Flash Cards
Methods of Teaching :
- Class Discussion
- Group Discussion
- Asking Questions
- Role Modelling
- Role Delegation
Reference Materials :
- Scheme of Work
- Online Information
- 9 Year Basic Education Curriculum
Content Development :
Shape of the Earth
What is the shape of the earth? You might have the idea that the earth is flat.
The earth is not flat, as you would think; it is round (spherical) in shape.
It is one of the nine planets that revolve round the sun.
It consists of three
(i) Land – mountains, rocks, hills, grassland, dry land, forest, desert. This is
the part of the earth where human beings live.
(ii) Water – oceans, seas, rivers, lakes, streams. This covers about two-thirds of
(iii) Atmosphere – air, cloud. This is the mixture of gases that envelops the
earth i.e., the mixture of gases that surround the earth’s surface.
How do we know the earth is spherical?
We have good reasons to believe that the earth is round and not flat. The
following are some of the reasons:
(i) When a ship appears the horizon, the top of the mast is seen before any
other part owing to the curvature of the earth.
(ii) We know that the sun rises at different times in different places.
If the earth were flat, the sun would rise at the same time in all places.
(iii) When we take pictures from high altitudes through a telescope, the
pictures show clearly that the earth is curved or spherical. It is not flat.
(iv) Nobody has seen the edge of the earth; if it was flat people would have
seen the edge.
The Earth’s Gravitational Pull
When something falls to the ground we say that it is pulled by a force. This
force is known as the force of gravity. This means that the earth exerts a force
on bodies that tends to pull these bodies towards the ground. This force is
called gravitational force. Therefore any object thrown up would eventually
come back to the ground because the force of gravity pulls it towards the
Weight of objects on Earth
The effect of the pull of the earth on an object is measured by its weight. The
greater the amount of matter an object contains, the greater its weight.
Another name for the amount of matter is mass. The mass of an object is
constant but the pull of the earth (known as gravity) varies from place to
Thus the weight of an object depends on the gravity:
Weight (W) = mass (m) x gravity (g)
For example, a bag full of tubers of yam will weigh more than an empty bag of
the same size if measured at the same place.
Weight of Objects on the Moon
Scientists have found out that the earth is nearly four times as big as the
moon, and that the weight of the earth is six times the weight of the moon.
The moon, like the earth, exerts a pull on objects around it. The force of
gravity of the moon is one sixth of the force of gravity of the earth. So an
object that weighs 120 N on the earth will weigh only 20N on the moon. This
means that an object weighs much less on the moon than it weighs on the
earth. Despite this fact, the object still has the same mass.
The sky is the space we look up to from the earth. It is the space high above
the earth. It is farther than we can see. The sky immediately above us is blue
owing to the earth’s atmosphere.
Beyond this blue sky is the boundless black sky that we simply refer to as
Objects that can be seen in the sky (space) are: the sun, the stars, the moon
and the other planets. The sun gives light both to the earth and moon. The
moon revolves around the earth; therefore it is called the earth’s satellite. This
means that a satellite is described as an object that revolves round (orbits) a
larger object. Jupiter, a planet, has as many as twelve satellites revolving
Space Travel is the journeying of a space traveler, otherwise known as an
astronaut, to explore the environment (space) outside the earth.
Scientists who study space and the objects we can find in it are called
One place that an astronaut can travel to is the moon. We have learnt that
objects weigh much less on the moon than they weigh on the earth. This is
why an astronaut wears a heavy space jacket so that he can walk on the moon.
Even with the space jacket, an astronaut often hops about as if he cannot walk
normally as he does on the surface of the earth
If an astronaut can jump one metre on earth, he will be able to jump six
metres on the moon, because the pull of the moon’s gravity on him is very
The Sun as a Major Source of Energy
The sun is a huge ball of burning gas. It is about 150 million kilometers from
The brightness of the day, which gradually comes in as the sun rises from the
east, shows that the sun is a source of light. Light and heat travel through
space. The rays reach us by radiation and they heat up the earth.
Number of Planets in The Solar System
Scientists have made us to believe from time immemorial that there are nine planets in the solar system but of recent based on recent researches and findings , the number has change . Read More
The topic is presented step by step
The class teacher revises the previous topics
He introduces the new topic
The class teacher allows the pupils to give their own examples and he corrects them when the needs arise
The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.
The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.
He or she does the necessary corrections when and where the needs arise.
1 . What is the shape of the earth
2. What is gravity
3. List the planets that make up the solar system
4, What is the major source of earth energy
5. What is space travel
Prepare for the next lesson by reading about THE EARTH’S MOVEMENT AND ITS EFFECTS