Index and Indices – Primary 5 Mathematics Lesson Note

Learn the meaning of index and indices in Primary 5 Mathematics with simple examples, class activities, FAQs, and Lagos State curriculum guide.

Primary 5 Mathematics lesson on index and indices. Includes meaning, examples, activities, evaluation questions, and Lagos curriculum alignment.

Lesson Plan Presentation

Subject: Mathematics
Class: Primary 5 (Basic 5)
Term: First Term
Week: 3
Age: 9–10 years
Topic: Index and Indices
Sub-topic: Understanding Index and Indices and Simple Applications
Duration: 40 minutes

Behavioural Objectives

By the end of the lesson, pupils should be able to:

Define the terms index and indices.
Recognise the index form of a number.
Write numbers as repeated multiplication using indices.
Interpret and read index notation.
Solve simple problems involving index and indices.

Keywords

Index, Indices, Power, Exponent, Base, Repeated Multiplication

Set Induction (Attention-Grabbing Story)

“Class, last Sunday after church, I saw Chika counting mangoes. Instead of saying ‘2 × 2 × 2 × 2 × 2,’ he just said ‘2 raised to the power 5.’ I smiled and thought, that’s a faster way to say it! Imagine if we had to say ‘3 × 3 × 3 × 3 × 3 × 3’ every time – we’d run out of breath! That short way of writing repeated multiplication is what we are learning today – Index and Indices.”

This story gets pupils curious and connects to something they can picture.

Entry Behaviour

Pupils already know how to multiply whole numbers and write them in short form.

Learning Resources & Materials

Chalkboard/Whiteboard
Marker/Chalk
Flashcards showing repeated multiplication and their index form
Multiplication tables
Small objects (bottle tops, beads) for demonstration

Building Background / Connection to Prior Knowledge

Ask pupils to recall multiplication from the last lesson. Write “2 × 2 × 2” and ask if they know a shorter way to write it. Introduce the word “index.”

Embedded Core Skills

Problem-solving
Mathematical reasoning
Logical thinking
Communication skills

Reference Books

Lagos State Unified Scheme of Work for Mathematics, Primary 5
New General Mathematics for Primary Schools (Book 5)
Nelson Mathematics for Primary 5

Instructional Materials

Multiplication chart
Index notation posters
Flashcards with examples

Content Development

Meaning of Index and Indices

Index means the small number written above and to the right of another number to show how many times it is multiplied by itself.
The bigger number is called the base.
The small number is called the index or power.
Indices is the plural form of index.
Index form is a short way of writing repeated multiplication.
Example: $2^4 = 2 × 2 × 2 × 2$ .
It is used to make writing and reading numbers faster.
Indices are used in mathematics, science, and even computing.
In $a^n$ , “a” is the base and “n” is the index.
Indices save time and space in mathematical writing.

Examples

$2^3 = 2 × 2 × 2 = 8$
$3^2 = 3 × 3 = 9$
$5^4 = 5 × 5 × 5 × 5 = 625$
$4^1 = 4$
$10^2 = 10 × 10 = 100$
$6^3 = 6 × 6 × 6 = 216$
$7^2 = 7 × 7 = 49$
$9^3 = 9 × 9 × 9 = 729$
$8^2 = 8 × 8 = 64$
$2^5 = 2 × 2 × 2 × 2 × 2 = 32$

Presentation Structure

Teacher’s Activities

Revise the last topic (Notation of Numbers).
Introduce the new topic using the mango story.
Explain the meaning of index and indices.
Show the base and index in examples.
Demonstrate how repeated multiplication is written in index form.
Give pupils guided practice.
Correct mistakes and explain difficult points.

Learners’ Activities

Listen to the teacher’s explanation.
Repeat the definition of index and indices.
Identify base and index in given examples.
Practise writing repeated multiplication in index form.
Ask and answer questions.

Class Activity Discussion (FAQs)

Q: What is an index?
A: A small number that shows how many times the base is multiplied by itself.
Q: What is the plural of index?
A: Indices.
Q: In $3^4$ , what is the base?
A: 3.
Q: In $3^4$ , what is the index?
A: 4.
Q: What is $2^3$ in repeated multiplication?
A: 2 × 2 × 2.
Q: Is $4^1 = 4$ ?
A: Yes.
Q: Which is bigger, $3^3$ or $4^2$ ?
A: $3^3$ = 27, $4^2$ = 16, so $3^3$ is bigger.
Q: Why do we use index form?
A: It saves time and space.
Q: Can index form be used in science?
A: Yes.
Q: Is $5^0$ equal to 1?
A: Yes, any number to the power of zero is 1.

Evaluation Questions (MCQ – Fill in the Blanks)

The small number written above a base is called the _____.
a) Base b) Index c) Digit d) Value
The plural of index is _____.
a) Indexes b) Indices c) Powers d) Multiples
$2^4$ means _____.
a) 2 × 2 × 2 × 2
b) 2 + 4
c) 4 × 4
d) 2 × 4
In $5^3$ , the base is _____.
a) 5 b) 3 c) 8 d) 125
In $7^2$ , the index is _____.
a) 7 b) 2 c) 49 d) 5
$3^2$ is equal to _____.
a) 6 b) 9 c) 8 d) 12
Which is larger: $4^2$ or $3^3$ ?
a) $4^2$ b) $3^3$ c) Same d) None
$10^2$ is equal to _____.
a) 20 b) 100 c) 1,000 d) 2
The base in $8^3$ is _____.
a) 8 b) 3 c) 11 d) 24
We use indices to write _____ multiplication in short form.
a) Addition b) Repeated c) Division d) Subtraction

Assessment (Short Answer)

Define index.
Define indices.
Write $2 \times 2 \times 2 \times 2$ in index form.
Write $5^3$ in repeated multiplication.
Identify the base in $9^4$ .
Identify the index in $9^4$ .
Calculate $4^2$ .
Calculate $3^3$ .
Which is bigger: $2^5$ or $5^2$ ?
Mention one place where indices are used in real life.

Conclusion

Teacher goes round the class to check and mark pupils’ work, correcting where necessary and praising efforts.

Internal Links

External Links

BBC Bitesize – Powers and Indices

Index and Indices – Primary 5 Mathematics First Term Lesson Note