Use of A.M. and P.M., Quantitative Aptitude Problems Involving Time for Primary 4

Class: Primary Four
Term: Third Term
Week: 5
Age: 9 years
Duration: 45 minutes
Subject: General Mathematics
Curriculum Theme: Mensuration
Focal competence: Calculating and telling time at any time of the day
Key competencies/values: Collaboration
Skills:

• Using time notation to solve time-related problems

Previous Lesson: Telling Time on the Clock, Reading Calendars and Writing Dates in Different Formats
Topic: Time: A.M., P.M. And Applications
Subject Matter: Use of a.m. and p.m, quantitative aptitude problems involving time

Specific Objectives

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

Cognitive Domain

• use the notation a.m. and p.m. for time of the day;
• solve problems of quantitative aptitude relating to time.

Affective Domain

• appreciate the importance of accurate time telling in daily life.

Psychomotor Domain

• accurately read and represent time from a clock using a.m. and p.m.

Reference Materials

The following resources were used in planning this lesson:

• 2025 Revised 9 Years Basic Education Curriculum
• Relevant State Unified Scheme of Work
• Primary Mathematics for Nigerian Schools, Book 4
• The HeadTeacher Scheme of work

Instructional Materials

The teacher will teach this lesson with the aid of:

• Clocks (analogue and digital)
• Calendar
• Clock charts

Rationale for the Lesson

Understanding A.M. and P.M. is fundamental for accurately communicating time and scheduling daily activities. This lesson equips pupils with the skill to interpret and solve practical problems involving time, which is essential for managing their routines and future academic tasks.

Prerequisite/Previous Knowledge

Pupils should be able to tell time on analogue and digital clocks, and understand basic units of time such as hours and minutes.

Lesson Content/Board Summary

Time: A.M., P.M. And Applications

Understanding A.M. and P.M.

Time is divided into two main parts using A.M. and P.M. to show whether it is morning, afternoon, evening, or night.

1. A.M. stands for “Ante Meridiem”, which means “before midday”. It covers the time from 12:00 midnight to 11:59 a.m. (noon).
2. P.M. stands for “Post Meridiem”, which means “after midday”. It covers the time from 12:00 noon to 11:59 p.m. (midnight).

Examples:

1. 7:00 a.m. is seven o’clock in the morning.
2. 2:30 p.m. is half past two in the afternoon.
3. 10:00 p.m. is ten o’clock at night.

Quantitative Aptitude Problems Involving Time

These problems require us to calculate durations, start times, or end times based on given information.

Example 1

Question: A train departs at 7:45 a.m. and arrives at its destination at 10:30 a.m. How long did the journey take?

Solution:

Step 1: Find the time from 7:45 a.m. to the next full hour (8:00 a.m.).

( 8:00 – 7:45 = 15 text{ minutes} )

Step 2: Find the time from 8:00 a.m. to 10:00 a.m.

( 10:00 – 8:00 = 2 text{ hours} )

Step 3: Add the remaining minutes to the arrival time.

( 10:30 – 10:00 = 30 text{ minutes} )

Step 4: Add all the durations.

( 2 text{ hours} + 15 text{ minutes} + 30 text{ minutes} = 2 text{ hours } 45 text{ minutes} )

Answer: The journey took 2 hours 45 minutes.

Example 2

Question: A student starts homework at 5:10 p.m. and finishes 1 hour 25 minutes later. What time did the student finish?

Solution:

Step 1: Add the hours to the start time.

( 5:10 text{ p.m.} + 1 text{ hour} = 6:10 text{ p.m.} )

Step 2: Add the minutes to the new time.

( 6:10 text{ p.m.} + 25 text{ minutes} )

( 10 text{ minutes} + 25 text{ minutes} = 35 text{ minutes} )

So, the time is ( 6:35 text{ p.m.} )

Answer: The student finished homework at 6:35 p.m.

Teaching Methods/Instructional Techniques

Discussion, Demonstration, Guided Practice, Question and Answer, Explanation, Problem Solving, Individual Practice

Instructional Procedures

Step 1: Introduction

Time: 5 minutes

Teaching Skill: Activating prior knowledge

Teacher’s Activity: The teacher greets the pupils and asks them to tell the current time using an analogue clock. The teacher then asks what they know about morning and afternoon times.

Pupils’ Activity: Pupils respond by telling the time and sharing their understanding of morning and afternoon.

Learning Point: Prior time knowledge

Step 2: Explanation of A.M. and P.M.

Time: 8 minutes

Teaching Skill: Explanation/Demonstration

Teacher’s Activity: The teacher explains the meaning of A.M. (Ante Meridiem) and P.M. (Post Meridiem), showing how they divide the day using a clock chart. The teacher clarifies that 12:00 a.m. is midnight and 12:00 p.m. is noon.

Pupils’ Activity: Pupils listen attentively and observe the clock chart, asking questions for clarification.

Learning Point: Meaning of A.M./P.M.

Step 3: Practical Application of A.M./P.M.

Time: 7 minutes

Teaching Skill: Guided Practice

Teacher’s Activity: The teacher gives examples of daily activities and asks pupils to state whether they occur in a.m. or p.m. (e.g., “When do you eat breakfast?”, “When do you watch evening news?”). The teacher writes various times on the board and asks pupils to add a.m. or p.m. correctly.

Pupils’ Activity: Pupils participate by identifying the correct A.M./P.M. for activities and writing them for given times.

Learning Point: Daily routine times

Step 4: Introduction to Time Problems

Time: 5 minutes

Teaching Skill: Problem Posing

Teacher’s Activity: The teacher introduces quantitative aptitude problems involving time by posing a simple word problem related to their school day, e.g., “If school starts at 8:00 a.m. and break time is 10:30 a.m., how long until break?”

Pupils’ Activity: Pupils think about the problem and suggest ways to solve it.

Learning Point: Time problem solving

Step 5: Worked Example 1

Time: 6 minutes

Teaching Skill: Demonstration/Explanation

Teacher’s Activity: The teacher works through Example 1 from the Board Summary on the board, explaining each step clearly and ensuring pupils understand how to calculate the duration between two times within the same A.M./P.M. period.

Pupils’ Activity: Pupils follow the teacher’s steps, ask questions, and copy the example into their notebooks.

Learning Point: First problem solution

Step 6: Worked Example 2 / Guided Practice

Time: 5 minutes

Teaching Skill: Guided Practice

Teacher’s Activity: The teacher works through Example 2 from the Board Summary, demonstrating how to find an end time given a start time and duration. The teacher then gives a similar simple problem for pupils to try individually or in pairs.

Pupils’ Activity: Pupils observe the solution, then attempt the practice problem, seeking help when needed.

Learning Point: Second problem solution

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

1. What does A.M. stand for?
2. What does P.M. stand for?
3. Is 9:00 in the morning a.m. or p.m.?
4. A football match started at 3:00 p.m. and ended at 4:45 p.m. How long did the match last?

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Time notation application

Step 8: Note-Taking

Time: 4 minutes

Teaching Skill: Guided Writing

Teacher’s Activity: The teacher guides pupils to copy the essential Board Summary notes on A.M./P.M. and the worked examples into their notebooks.

Pupils’ Activity: Pupils copy the notes carefully into their notebooks.

Learning Point: Board notes copying

Step 9: Conclusion

Time: 2 minutes

Teaching Skill: Consolidation

Teacher’s Activity: The teacher briefly reminds pupils of the importance of A.M./P.M. in daily life and encourages them to practice telling and calculating time regularly.

Pupils’ Activity: Pupils listen and acknowledge the importance of the lesson.

Learning Point: Time concepts reinforced

Continuous Assessment/Further Study

Type: Homework

Instruction: Solve the following problems in your mathematics notebook.

1. Write two activities you do in the a.m. and two activities you do in the p.m.
2. A bus left Lagos at 6:00 a.m. and arrived in Ibadan 2 hours 15 minutes later. What time did the bus arrive in Ibadan?
3. A child slept from 9:00 p.m. to 6:00 a.m. How many hours did the child sleep? (Hint: This problem crosses midnight. Calculate time from 9 p.m. to 12 a.m., then from 12 a.m. to 6 a.m. and add.)

Lesson Keywords

• A.M. – Ante Meridiem, time from midnight to noon.
• P.M. – Post Meridiem, time from noon to midnight.
• Time – The ongoing sequence of events from past to present to future.
• Quantitative Aptitude – Problems involving numerical reasoning and calculation.

Differentiation

Support for weaker learners: Provide weaker learners with pre-drawn clock faces to help them visualize time calculations. Focus on simple A.M./P.M. identification before moving to problems. Use a number line for time calculations.

Extension for faster learners: Challenge faster learners with more complex word problems involving time, such as those that cross the a.m./p.m. boundary or require multiple steps.

Suggested Lesson Videos

For further understanding, search for “A.M. and P.M. for kids” or “solving time word problems primary 4” on YouTube.

Teacher Guide for Using This Lesson Plan

Before the lesson, ensure you have a large classroom clock (analogue and digital if possible) and a clock chart showing the 24-hour cycle alongside A.M./P.M. notation. Begin by reviewing basic time-telling. Clearly explain the division of the day into A.M. and P.M., using practical examples from the pupils’ daily routines. When introducing quantitative aptitude problems, demonstrate the step-by-step solutions carefully, encouraging pupils to think aloud. Allow sufficient time for guided practice and individual problem-solving. Pupils should copy the Board Summary notes after the main teaching and practice activities are completed, typically in Step 8. Check for understanding frequently through questions during each step of the lesson and provide immediate feedback. For the homework, guide pupils on how to approach the problem that crosses midnight, if time permits, or provide it as a challenge.