Lesson Planning of Addition & Subtraction (Units of Time)
Subject Mathematics
Grade 4^{th}
Students` Learning Outcomes
 Add and subtract units of time without carrying / borrowing.
 Solve simple real life problems involving conversation, addition or subtraction of units of time.
Information for Teachers
 Units of time are: minutes and seconds.
 We can add or subtract only same units.
 1 hour = 60 minutes
 1 minutes = 60 seconds
 We multiply the number of hours by 60 to get minutes.
 We multiply the number of minutes by 60 to get sends.
Material / Resources
Writing board, chalk / marker, duster, models of analog and digital clocks [ real if possible], textbook
Introduction
 Ask the students how long are your lunch break? (Possible answer would be as; 30 minutes)
 After getting their responses ask them, can you tell this time in seconds? (Possible answer would be as; yes).
 If yes, then it is equal to how many seconds?
 Tell them to convert minutes into seconds we multiply minutes by 60.
 Show them a chart of clock and ask them: as;
 Look at the clock and ask what the time by now is? (Possible answer would be as; 11:10)
 What would be the time after 10 minutes and 15 minutes?
 Today we will study to add or subtract units of time and daily life examples.
Development
Activity 1
Hours Minutes 7 35 + 6 21 13 56
Hours Minutes Seconds 24 44 56 – 12 21 34 12 23 22 (1) 8 hours 29 minutes + 4 hours 12 minutes (2) 19 hours 31 minutes – 10 hours 20 minutes 
Activity 2
Hour Minute 2 25 – 1 15 1 10

 Recall the main concepts so students can further improve their deficiencies.
 1 hour = 60 minutes
 1 minutes = 60 seconds
 Hours can be converted to minutes by multiplying with 60.
 Only hours can be added to hour’s minutes to minutes and seconds to seconds.
 Assess the students with such sort of questions.
 Nadeem spends 1 hour 45 minutes to study and 2 hours 13 minutes to play. How much total time does he serves for both activities?
 Complete the following table.
No 
Day 
Time beginning 
Time ending 
Time spent at swimming practice 
1 
Sunday 
3 : 30 pm 
5 : 15 pm 
1 hour and 45 minutes 
2 
Monday 
5 : 00 pm 
6 : 30 pm 

3 
Tuesday 
4 : 45 pm 
6 : 15 pm 

4 
Wednesday 
5 : 40 pm 
6 : 45 pm 

5 
Thursday 
5 : 25 pm 
6 : 45 pm 

6 
Friday 
7 : 30 pm 
8 : 55 pm 

7 
Saturday 
11 : 10 am 
2 15 am 

8 
Sunday 
1 : 40 pm 
3 35 pm 

9 
Monday 
4 : 15 pm 
5 : 55 pm 

10 
Tuesday 
5 : 10 pm 
6 : 25 pm 

11 
Wednesday 
4 : 45 pm 
6 : 10 pm 

12 
Thursday 
5 : 25 pm 
7 : 40 pm 

13 
Friday 
5 : 40 pm 
6 : 55 pm 

14 
Saturday 
11 : 25 am 
1 : 55 am 

 Give some homework questions so students may be able to solve more real life examples.
 How much time you took for each payer and then add all the five times
 Calculate your breakfast, lunch and dinner times.
 Calculate time in which you reach to school from home and reach at home from school.