Lesson Planning of Addition & Subtraction (Units of Time) Subject Mathematics Grade 4th

 

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 Write the following on the board, as; 7 h, 35 m + 6 h, 21 minutes Ask the students how can we add these hours and minutes? Take their feedback and demonstrate on the board.        Hours          Minutes          7                    35                                                +    6                    21                                                    13                    56 Explain them that we write hours and minutes vertically in the columns. Hours are added to hours and minutes to minutes. Now let us see how we can subtract time? 24 hours 44 minutes 56 sends – 12 hours 21 minutes 34 seconds Ask them to solve the following questions : as;                 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 Give real life examples to further strengthen their concepts. Ask from Rabia. Your mother can cook rice and prepare salad n how much time? Suppose she says that rice in 2 hours 41 minutes and salad in 10 minutes. Can you calculate how much time she took altogether? Help in solving this question: as; Rice took   = 2 hours 41 minutes Salad took =              10 minutes Total time = 2 hours 41 minutes + 10 minutes = 2 hours 51 minutes. State another question as Raza completed his homework in 1 hour 15 minutes and Qasim took 1 hour 15 minutes. How much more time Raza took? Raza took = 2 hours 25 minutes Qasim took = 1 hour 15 minutes Difference between their times = 2 hours 25 minutes – 1 hour 15 minutes = 1 hour and 10 minutes.             Hour           Minute                2                25                -   1                 15               1                 10

Sum up / Conclusion

• 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

Follow up

• 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.