GRADE 5 MATHEMATICS – LESSON NOTE, Third Term (Week 1)
GRADE 5 MATHEMATICS – LESSON NOTE | NUE, NAPPS Scheme
Week: 1
Topic: Structure of the Earth
Duration: 1 Week (28th April – 2nd May)
Sub-topics:
(i) Introduction of shapes that are spherical
(ii) Shape of the Earth
(iii) Volume of the globe
(iv) Comparing volume of a sphere and cuboid
(v) Quantitative aptitude involving volume of a sphere and cuboid
Learning Objectives
By the end of the lesson, pupils should be able to:
- Identify objects that are spherical in shape.
- Describe the shape of the Earth as a sphere.
- Calculate the volume of a cuboid using the formula.
- Calculate the volume of a sphere using the formula.
- Compare the volumes of a sphere and cuboid.
- Solve real-life mathematical problems involving volumes.
Instructional Materials
- Globe
- Balls and oranges
- Measuring tape
- Cardboard boxes
- Rulers
- Diagrams and charts
- Whiteboard or chalkboard
Previous Knowledge
Pupils already know basic 3D shapes and simple multiplication.
Lesson Presentation
Sub-topic 1: Introduction of Shapes that are Spherical
Explanation:
Spherical shapes are round in all directions. Examples include balls, oranges, globes, and balloons.
Class Fun (Class Work):
Draw and name three spherical objects.
Home Fun (Assignment):
Look around your home and list 3 things that are spherical in shape.
Sub-topic 2: Shape of the Earth
Explanation:
The Earth is spherical in shape. Although it may not be a perfect ball, it is round like a globe. This is why globes are used to represent the Earth.
Class Fun:
Observe a globe and describe its shape in your own words.
Home Fun:
Write two reasons why a globe is used to represent the Earth.
Sub-topic 3: Volume of the Globe (Sphere)
Formula:
Volume of a sphere = 4/3 × π × r³
Let π = 3.14
Example Calculation:
Find the volume of a globe with radius 3 cm.
V = 4/3 × 3.14 × 3³ = 4/3 × 3.14 × 27 = 113.04 cm³
Class Fun:
Use the formula to calculate the volume of a sphere with radius 4 cm.
Home Fun:
Calculate the volume of a sphere with radius 2.5 cm.
Sub-topic 4: Comparing Volume of a Sphere and Cuboid
Formula for cuboid volume:
Length × Width × Height or Length x Breadth x Height
Example:
Sphere radius = 3 cm → Volume = 113.04 cm³
Cuboid = 5 cm × 5 cm × 5 cm = 125 cm³
Conclusion: Volume of cuboid is greater than that of the sphere.
Class Fun:
Compare volumes of a sphere (r = 2 cm) and cuboid (l = 4 cm, w = 3 cm, h = 2 cm)
Home Fun:
Explain why a cuboid can contain a sphere inside it.
Sub-topic 5: Quantitative Aptitude Involving Volume
Word Problem Example:
A water tank is a cuboid measuring 6 cm by 5 cm by 4 cm. What is its volume?
Volume = 6 × 5 × 4 = 120 cm³
Class Fun:
Solve: What is the volume of a cuboid with dimensions 3 cm × 4 cm × 2 cm?
Home Fun:
A spherical balloon has a radius of 2 cm. What is its volume?
Pupils’ Activities
- Identifying spherical objects
- Describing Earth as a sphere
- Calculating volumes of cuboids and spheres
- Comparing and discussing the volumes of shapes
Teacher’s Activities
- Display globes, balls, and cuboids
- Explain concepts using formulas and real-life items
- Guide pupils in solving volume problems
- Evaluate pupils using questions and exercises
Assessment / Evaluation Questions
- What is the shape of the Earth?
- Write two examples of spherical objects.
- Find the volume of a cuboid with l = 3 cm, w = 2 cm, h = 4 cm.
- Calculate the volume of a sphere with radius 2 cm.
- Which has greater volume: a cuboid with volume 120 cm³ or a sphere of 113 cm³?
Conclusion
The Earth is spherical in shape. We can find and compare volumes of shapes like spheres and cuboids using formula.