LESSON PLANNING OF SOLVE REAL LIFE PROBLEMS INVOLVING CONVERSION, ADDITION AND SUBTRACTION OF THE UNITS OF TIME

Subject Mathematics

Grade 5^{th}

Students` Learning Outcomes

- Solve real life problems involving conversion, addition and subtraction of the the time.

Information for Teachers

Each day is made up of 24 hours.

A day ends at 12 midnight and a new day begins at the same time at midnight.

The time between 12 midnight and 12 noon is called a.m.

The time between 12 noon the 12 midnight is called p.m.

The abbreviation of ‘a.m.’’ stands for ‘ante-meridian’ [before midday]

The abbreviation of ‘p.m.’’ stands for ‘post-meridian’ [after midday]

**For addition of time:**

The same units are added i.e.

o Hours can be added to hours; e.g.: 3 hours + 9 hours.

o Minutes can be added to minutes; e.g.: 25 minutes + 32 minutes.

o Second can be added to seconds; e.g.: 33 seconds + 21 seconds

If there are two different units of time are given then one will be converted into the other before adding. For example:

o 6 hours + 72 minutes

o 6 x 60 = 360 minutes

o 360 minutes + 72 minutes = 432 minutes

o Again convert it in hours and minutes by divide with 60432 ÷ 60 = 7 hours 20 minutes.

**For subtraction of time:**

- The same traditional method of carrying will be used, but carrying will be done from hours or minutes as 60.
- For example

- Key words:
- Time, measurement, hours, minutes, telling time
- During lesson teacher will be consult with textbook at all steps when and where required.

Material / Resources

Writing board, chalk / marker, duster, a chart on which problems are written and cut into strips, so that whole class can focus on one problem at a time, textbook

Introduction

- Begin the lesson by eliciting from students, “how time is used in their daily lives?”
- Students may suggest the following:

o Time spent in reciting The Holy Quran.

o Time spent in playing.

o The times when school starts and ends.

- Explain to the students that they are using math all the time. For example; when they figure out how much time or money they have, spent, or needed.
- During this less, students will be working together to apply the mathematical skills they have already learnt [addition, subtraction, multiplication, and division], to solve real –life problems about time.
- They will begin by working as a whole class to solve problems about time.
- After practicing, students will work with peers and apply the same mathematical skills to prepare their own questions / word problems involving time. [Each pair will prepare one question / word problems]

Development

Activity 1

- Display / stick the strip of the following word problem on the board.

- Discuss the way to solve the problem with the whole class.
- Which operation must they use?
- Let them identify the need to use subtraction to determine that:

o One hour earlier than 3:45 would be :45

o Subtracting another 15 minutes would bring the time to ;30

o So to reach to the ground to get to practice on time, Salem and his brother must leave at 2:30.

- Invite the students in pairs to write different steps/statements of the above mentioned word problem on the board and find the final answer;

Solution:

- Give them more examples.

Activity 2

- Divide students into the groups of three or four.
- Based on what they have learnt during word problems of time, ask them to list three tips for other students on how to solve word problems. The chart would encourage students to do the following while solving word problems:
- o Read the problems very carefully
- o Point out key words that signify which operation to use.
- o Discuss the importance of showing the steps involved in solving a problem.
- Let students solve the following problems with their peers—once they talk about the process involved in solving the problems.

- After reviewing the problems, distribute to each student a copy of the work sheet on per student, or give strips of questions to each pair.
- Students should work independently to solve each word problems on the work sheet.
- Review the problems in class.

Activity 3

- Discussion questions (Whole class)
- Ask the students;
- Which words in a word problem usually means that addition is the correct operations to use?
- Which word usually indicates that subtraction should be used?
- Give two examples about money and time from your everyday life , make their questions and ask: “can you solve them?”

Sum up / Conclusion

How many hours are there in a day? [24 hours]

When the day ends? [12 midnight]

What we said the time between 12 noon to 12 midnight a. m. / p.m.? [p. m.]

What do you mean by pm? [Prime meridian]

What do you mean by ‘am’? [Anti-meridian]

Assessment

- Ask some mental math questions:

o 70 minutes = ……. Hours ……. Minutes

o 8 weeks = …………………………..months

o What is the time now?

o What time will it be after 45 minutes? After 70 minutes? After 12 minutes; etc.

- Ask few more questions from the class and let them solve together.
- Students are required to answer at least 4 of the 5 questions on the work sheet.
- Answer key: for “Got the Time” work sheet.
- Teacher must involve the students to solving the exercise questions at the end of the lesson of the textbook

Follow up

- Make your time table and identify which part of the day or week you don`t plan and use effectively/.
- Remember to keep time for playing, watching TV and helping mom in the kitchen or helping young siblings, etc.
- Make a prayer chart for the whole month and record how many prayers you offer every day and calculate at the end of the month.

Directions:

- Read each of the story problems given below. Pay special attention to the times mentioned in each story. Answer the question at the end of each story problem.