In Elementary Mathematics Grade 2

Lesson Guide

In

Elementary Mathematics

Grade 2

Reformatted for distribution via DepEd LEARNING RESOURCE MANAGEMENT and DEVELOPMENT SYSTEM PORTAL

DEPARTMENT OF EDUCATION BUREAU OF ELEMENTARY EDUCATION

in coordination with ATENEO DE MANILA UNIVERSITY

2010

Chapter I

Whole Numbers

Subtraction

INSTRUCTIONAL MATERIALS COUNCIL SECRETARIAT, 2011

Lesson Guides in Elementary Mathematics Grade 2 Copyright © 2003 All rights reserved. No part of these lesson guides shall be reproduced in any form without a written permission from the Bureau of Elementary Education, Department of Education.

The Mathematics Writing Committee

GRADE 2

Region 4 Teresita O. Plata – Cavite Erlinda F. Zinampan – Rizal Rosalinda R. Ravelas – Laguna Sheilaver O. Capumpon – Cavite National Capital Region (NCR) Flordelina A. Alquiza – Regional Office, NCR Marites A. Asuque – Taguig/Pateros Praxedes F. Mendoza – Makati Victoria V. Figueroa – Valenzuela Aurora P. Portes – Manila Bureau of Elementary Education (BEE) Noel P. Miranda Robesa R. Hilario

Ateneo de Manila University Virgie C. Gayda

Support Staff Ferdinand S. Bergado Ma. Cristina C. Capellan Emilene Judith S. Sison Julius Peter Samulde Roy L. Concepcion Myrna D. Latoza Marcelino C. Bataller Eric S. de Guia – Illustrator

Consultants Fr. Bienvenido F. Nebres, SJ – President,

Ateneo de Manila University Carmela C. Oracion – Ateneo de Manila

University Pacita E. Hosaka – Ateneo de Manila

University

Project Management

Yolanda S. Quijano – Director IV Angelita M. Esdicul – Director III

Simeona T. Ebol– Chief, Curriculum Development Division Irene C. de Robles– OIC-Asst. Chief, Curriculum Development Division

Virginia T. Fernandez – Project Coordinator

EXECUTIVE COMMITTEE

Jesli A. Lapus – Secretary, Department of Education Jesus G. Galvan – OIC, Undersecretary for Finance and Administration

Vilma L. Labrador – Undersecretary for Programs and Projects Teresita G. Inciong – Assistant Secretary for Programs and Projects

Printed By: ISBN – 971-92775-1-3

iii

TABLE OF CONTENTS

Introduction ............................................................................................................................ iv Matrix .................................................................................................................................. v

I. WHOLE NUMBERS

Subtraction

Subtraction through Illustration .................................................................................. 1 Finding the Missing Addend ...................................................................................... 5 Subtracting 2- to 3-Digit Numbers:

without Regrouping ........................................................................................ 7

with Regrouping in the Tens Place ................................................................. 12

with Regrouping in the Hundreds Place and with Zero Difficulty ................................................................................. 14

with Regrouping in the Tens and Hundreds Place and with Zero Difficulty ................................................................................. 18

Using Addition to Check Subtraction ......................................................................... 22 Subtracting Mentally with Minuends up to 50 without Regrouping .............................. 25 Analyzing 1-Step Word Problems

What is Asked, Given, Word Clues and Operation to be Used ......................... 27

Transforming Word Problems into Number Sentences and Stating the Complete Answer .................................................................. 30

Analyzing 2-Step Word Problems

Telling What is Asked, Given, Word Clue, Hidden Question and Operations to be Used .......................................................................... 34

Transforming Word Problems into Number Sentences and Stating the Complete Answer ................................................................. 37

iv

I N T R O D U C T I O N

The Lesson Guides in Elementary Mathematics were developed by the

Department of Education through the Bureau of Elementary Education in

coordination with the Ateneo de Manila University. These resource materials

have been purposely prepared to help improve the mathematics instruction

in the elementary grades. These provide integration of values and life skills

using different teaching strategies for an interactive teaching/learning

process. Multiple intelligences techniques like games, puzzles, songs, etc.

are also integrated in each lesson; hence, learning Mathematics becomes fun

and enjoyable. Furthermore, Higher Order Thinking Skills (HOTS) activities

are incorporated in the lessons.

The skills are consistent with the Basic Education Curriculum

(BEC)/Philippine Elementary Learning Competencies (PELC). These should

be used by the teachers as a guide in their day-to-day teaching plans.

v

MATRIX IN ELEMENTARY MATHEMATICS Grade 2

COMPETENCIES VALUES INTEGRATED STRATEGIES USED MULTIPLE INTELLIGENCES

TECHNIQUES With HOTS

C. Comprehension of Subtraction

1. Subtract 2- to 3-digit numbers with minuends up to 999 without and with regrouping

1.1 Illustrate how subtraction is used when:

1.1.1 Taking away from the given set

Cooperation Concept development, Modeling, Acting out the problem, Cutting pictures

Numbers, Manipulative, Skits and play, Cooperative groups

1.1.2 Finding a missing addend Patience Concept development, Write a number sentence, Acting out the problem

Manipulative, Cooperative groups, Independent study, Skits and play

1.2 Subtract 2- to 3-digit numbers without regrouping

Frugality Concept development, Pictures, Simplifying the problem

Numbers, Drawing, Cooperative groups, Manipulative

1.3.1Subtract 2- to 3- digit numbers with regrouping in the tens place without or with zero difficulty

Courtesy Concept development, Write a number sentence, Acting out

Numbers, Scientific method, Games, Speaking, Skit/Dialogue

1.3.2 in the hundreds place value without or with zero difficulty

Cooperation Acting out, Concept development, Puzzle

Games, Drawings, Cooperative groups

1.3.3 in the tens and hundreds place without or with zero difficulty

Obedience Concept development Numbers, Scientific method, Self awareness activity, Reading, Writing, Charts, Games, Cooperation groups

2. Use addition to check subtraction Sharing Use objects, Write a number sentence

Scientific method, games, reading, Real world connections

3. Subtract mentally 1-digit number from 1 and 2 digit numbers with minuends up to 50 without regrouping

Love for parents Concept development, Pattern

Game, Numbers

4. Application of Subtraction 4.1 Solve 1-step word problems involving

subtraction of whole numbers including money with minuends up to 999 without and with regrouping

4.1.1 Analyze the word problem 4.1.1.1 Tell:

what is asked

what is/are given

the word clue/s

the operation to be used

Enjoyment in reading Concept development, Simplifying the problem, Working back

Cooperative groups, Story telling, Reading, Writing

4.1.2 Transform the word problem into a number sentence

Thrift Concept development, Simplifying the Problems, Write a number sentence

Numbers, Games, Reading Classifying, Real world connections

4.1.3 Use the correct operation 4.1.4 State the complete answer

vi

5. Application of Addition and Subtraction 5.1 Solve 2-step word problems involving

addition and subtraction of 2- to 4-digit numbers including money

5.1.1 Analyze the word problems 5.1.1.1 Tell:

what is asked

the word clue/s

the hidden question

the operation to be used

Industry Concept development, Write a number sentence

Numbers, Reading, Cooperative groups

5.1.2 Transform the word problem into a number sentence

Industry Concept development, Acting out, Guess and check, Simplifying the problem

Skits and play, Cooperative groups, Reading, Writing, Speaking, Independent study

5.1.3 Use the correct operation 5.1.4 State the complete answer

1

Subtraction through Illustration

I. Learning Objectives

Cognitive: Illustrate how subtraction is used when taking away from a given set Psychomotor: Play the situations to illustrate a subtraction sentence Affective: Show cooperation in any group activities

II. Learning Content

Skill: Subtraction through illustration Reference: BEC - PELC I.C1.1.1 Materials: counters, flash cards for drill, activity cards, magazines/newspapers Value: Cooperation

III. Learning Experiences

A. Preparatory Activities

1. Drill

a. 9 b. 8 c. 5 d. 12 e. 13 f. 15 g. 18 h. 48 + 9 + 6 + 7 + 5 + 8 + 32 + 36 + 7

2. Motivation (The pupils use their counters as they act out the word problems that their teacher will read. The pupils work in pairs.)

You have 35 marbles before you played marbles with Gilbert. In the end of the game, you gave 18 of your marbles to him. How many of your marbles were left?

- How many marbles did you have before playing with Gilbert? - How many marbles did you give to Gilbert? - What happened to your marbles? - Did they increase or decrease in number? - How many of your marbles were left?

B. Developmental Activities

1. Presentation

Present the number sentence 35 – 18 = 17

Ask: What do you call 35? What do you call 18? What do you call 12?

2

Show the class how subtraction is done using illustration.

Example 1: 35 – 18 = ___

Example 2: 12 – 7 = ___ Ask the pupils to give the subtraction sentence in the next example.

2. Group Activities

Activity 1

Divide the class into five groups. Each group should have different number of members.

Tell the pupils to act out the situation in the activity card that would illustrate the following subtraction sentence.

Group 1: 8 – 3 = Situation: Eight birds are sitting on the fence. Three of the birds flew

away. How many birds remained sitting on the fence?

Group 2: 10 – 4 = Situation: Ten boys and girls are playing basketball. After a while, 4 of

them were called by their teacher. How many children were left?

Group 3: 5 – 2 = Situation: There were 5 children dancing the “Statue Dance”. When the

music stopped, 2 were found blinking, so they were excluded from the contest. How many children were left on the dance floor?

Group 4: 6 – 3 = Situation: Six boys were asked to roll-up like eggs. When the leader

says “Go!”, only 3 of them were able to do it. How many boys failed to do it?

35 marbles

18 marbles

35 – 18 = 17 marbles

12 smileys

7 smileys

12 – 7 = 5 smileys

3

Group 5: 11 – 7 = Situation: There were 11 standing passengers on the bus. Seven of

them got off from the bus stop. How many standing passengers were left?

Activity 2

Group the pupils by 5s.

Each group will cut pictures from magazines and newspapers that would illustrate the subtraction sentence in their activity cards.

Activity Card

Direction: Cut pictures from magazines/newspaper to illustrate the subtraction sentence below:

9 – 4 = ___

Activity Card Direction: Cut pictures from magazines/newspaper to illustrate the subtraction sentence below:

13 – 8 = ____

(paste your pictures here)


Activity Card Direction: Cut pictures from magazines/newspaper to illustrate the subtraction sentence below

10 – 5 = ___

Activity Card Direction: Cut pictures from magazines/newspaper to illustrate the subtraction sentence below

7 – 3 = ____



Activity Card Direction: Cut pictures from your Magazines/newspaper to illustrate the subtraction sentence below

8 – 5 = ___


Presentation of the outputs of each group

*Valuing: - How did you come up with beautiful outputs? - Did each one of you cooperate with one another? - How should we work with the group to make our activity successful?

4

3. Generalization

How can we illustrate subtraction from given sets?

C. Application

Pupils do the exercises in their Mathematics notebook.

Choose a number sentence. Draw a picture about it. Then write the answer of the number sentence to make it complete.

1. 12 – 6 = 3. 6 – 2 = 5. 9 – 4 =

2. 15 – 8 = 4. 8 – 4 = 6. 10 – 5 =

IV. Evaluation

A. Illustrate the following subtraction sentences. Then answer the number sentence.

Example:

1. 5 – 3 = 2 2. 6 – 1 = 5

3. 9 – 3 = 6 4. 8 – 5 = 3 5. 4 – 2 = 2

B. Write the subtraction sentences for the following illustrations:

1.

2.

3.

4.

5.

4 – 2 = 2

=

=

=

=

=

5

V. Assignment

Illustrate the following subtraction sentences. You may draw or cut pictures from magazines or newspapers. 1. 8 – 3 = 5 2. 3 – 1 = 2 3. 7 – 2 = 5 4. 5 – 2 = 3 5. 10 – 3 = 7

Finding the Missing Addend


Cognitive: Illustrate how subtraction is used when finding the missing addend Psychomotor: Write subtraction sentence from an addition sentence Affective: Practice working patiently


Skill: Finding the missing addends Reference: BEC PELC – I C1.1.3 Materials:

flash cards – basic subtraction facts whose minuends are up to 18

activity cards for slow learners

counters Value: Patience



1. Drill - Basic subtraction facts with minuends up to 18.

Example: 12 - 8 = 15 - 6 =

7 - 8 = 14 - 6 =

Compare the following number sentences.

16 - 4 1 3 - 7 20 - 5 3 5 - 20 56 - 14 60 -30

2. Motivation

Luis placed 8 pencils in his pencil case. He went to the kitchen to drink water. When he returned, he found his pencil case full of pencils. Then he heard his brother say: "I put some of my pencils in your pencil case." Luis counted all the pencils and found 15 pencils in all.

6


1. Presentation

Call on a pupil, (Pupil A) to act out the role of Luis and another pupil, (Pupil B) to act as the brother.

- How many pencils did Luis (Pupil A) place in his pencil case? (Write the

number 8 on the board) - What did the brother do? What operation is related to it?

(Write it after 8) 8 + - How many pencils were in the pencil case when Luis returned and

counted the pencils? (Write it opposite 8.) 8 + 15

- Did the story tell the number of pencils his brother placed in the pencil case? (Draw a box to represent the answer)

(Write the number sentence for the word problem.) 8 + = 15

- How many pencils did his brother place in his pencil case? - How did you get the answer? - Discuss to the class how subtraction is used to find a missing addend. - To find the missing addend, remove 8 from 15. The process is

subtraction.

8 + = 15 15 – 8 = 7

2. Group Activities

Activity 1

Group the pupils by 3s.

Distribute activity cards.

With the aid of their counters, let them solve for the missing addends.

12 + = 19 + 15 = 23

Activity 2

Individually, the children

construct 2-3-digit addition sentences

Make 2 subtraction sentences for each addition sentence. Example: A: 250 + 206 = 456 S: 456 – 206 = 250 456 – 250 = 206

Presentation of output.

*Valuing: - How did each one of you work in your activity? - Did you find it difficult? How were you able to come up with the

solution and solve the problem? - Were you noisy or quiet? What does it mean by being patient?

That could be the reason why your outputs are well done. Remember that any work patiently done is work well done.

3. Generalization

What operation is used when finding a missing addend?

C. Application

1. Write the subtraction sentence to find the missing addend.

a. 48 + = 79 d. 642 + = 842

7

7

b. + 345 = 589 e. 923 + = 950 c. + 205 = 565 f. + 521 = 986

2. Subtract to find the missing addend.

a. 75 + ___ = 145 b. ___ + 95 = 180 c. 48 + ___ = 129 d. 88 + ___ = 165 e. 94 + ___ = 210

IV. Evaluation

Find the missing addend for each item. Then write the subtraction sentence from the following addition sentences.

1. 386 2. 3. 4. 702 5. 5. + + 154 + 38 + + 336 890 241 459 984 745

V. Assignment

Write the subtraction sentence to find the missing addend. Write the missing addend in the box.

1. 48 + = 179 Subtraction: 2. + 522 = 864 Subtraction: 3. + 84 = 189 Subtraction: 4. 257 + = 689

Subtraction: 5. + 213 = 596

Subtraction:

Subtracting 2- to 3- Digit Numbers without Regrouping


Cognitive: Subtract 2- to 3-digit numbers from 2- to 3-digit numbers without regrouping

Psychomotor: Write subtraction sentences correctly Affective: Use money wisely


Skill: Subtracting 2- to 3-digit from 2- to 3- digit numbers without regrouping

Reference: BEC PELC I C 1. 2 Materials: charts, flats, longs and ones, domino cards Value: Frugality

8



1. Drill Identify which operation is used to make the sentence true. Let the pupils raise their right hand if the answer is plus (+) and their left hand if the answer is minus (-). a. 8 b. 3 c. 9 d. 2 e. 12 6 4 3 8 3 2 7 6 10 15 f. 7 g. 6 h. 1 i. 10 j. 4 3 0 8 5 2 4 6 9 5 6

2. Review Let the pupils (individual or pair) climb up the „stairs‟ and write the answer on each step by adding the numbers correctly. e. d. c. b. a. Review the terms in subtraction. Let the pupils identify and define each term in subtraction. Example: 7 – 2 = 5 difference minuend subtrahend

3. Motivation

How much is your daily allowance? Do you spend all your money? Why or why not? About how much do you save each day? What do you do with your daily savings? Why is it good to save money?


1. Presentation

Present the word problem.

Jenny saves a part of her daily allowance. She has saved 78. She spent 55 to buy a gift for her mother‟s birthday and saved the rest. How much did she save? *Valuing:

- Who saved money? - How much did she save? - What did she do with her money? Why? - What kind of a girl is Jenny?

148 + 327

53 + 72

18 + 26

316 + 242

24 + 35

9

Discussion a. What is asked in the problem? b. What are the given facts? c. How are you going to solve it? d. What is the correct number sentence?

Can you guess what is the answer? Let the pupils give their guesses. Let them check their answers using flats, longs and ones.

1 flat = 100 1 long = 10 1 ones = 1

Mechanics: a. Identify the minuend and the subtrahend. Identify the place value of

each digit. b. Express the minuend (ex. 78) using flats, longs and ones.

78 =

c. Let one pupil hold the 7 longs and 8 ones. Ask: How many will you give away? 55

Let the pupil give the 55 to his/her partner. d. Let them start giving the ones then the longs.

8 ones – 5 ones = 3 ones 7 longs – 5 longs = 2 longs

How many longs and ones were left? So, 78 – 55 = _____.

In subtracting 55 from 78, in what place value did we start subtracting?

2. Group Activities Pair Activity Activity 1

Solve 246 – 134 = N by using the flats, longs, and ones. The pupils may be given time to do this on their own or the teacher will still guide them. Let the pupils discuss the process to their partners then later to the class.

7 longs 8 ones

10

Give another example (this time without using the flats, longs and ones). Guide them to start subtracting from ones, then tens and then hundreds.

Example: a.) 583 – 241 = N b.) 645 – 320 = N

a. b.

H T O H T O

5 8 3 6 4 5

-2 4 1 -3 2 0

3 4 2 3 2 5

Activity 2

Game Card The teacher will make cards such that when pupils will use them they will not encounter regrouping. How to use Card Game a. Two cards will be given to each pupil. Have him/her combine the two.

Example:

b. Let them identify which domino card has a higher number then let them

subtract the domino card with the smaller number. Example:

148 -

124 24

c. Have your pupils find a partner. Guide them to start subtracting from the

ones then the tens. d. Allow the pupils to play with their cards to come up with different

subtraction sentences. Let them share these to the class. * If the pupils can already subtract 2-digit by 2-digit numbers then the teacher can already give 3-digit numbers Example: 366 813 526 - 52 - 401 - 315 Guide them again to start subtracting from ones then tens and finally to hundreds.

Activity 3 Divide the class into 4 groups. Give each group an activity card. Answer the questions.

What is 41 subtracted from 653?

30 2

140 8

120 4

11

What is 486 minus 242?

What is 965 less than 442? What is the difference between 847 and 225?

3. Generalization How do you subtract 2- to 3-digit numbers from 2- to 3-digit numbers without regrouping?

C. Application

1. Boyet saves money. He has already saved 34. The toy he wants to buy

costs 48. How much does he still need to save? 2. There are 256 pupils in Grade Two. If 124 pupils are girls, how many are

boys?

IV. Evaluation

A. Answer the following questions 1. What is the difference between 734 and 223? 2. What is 84 subtracted from 695? 3. What is 496 minus 232? 4. What is 965 decreased to 442? 5. What is the difference between 984 and 32?

B. Subtract.

1) 38 2) 81 3) 68 4) 75 5) 198

- 36 - 70 - 54 - 24 - 88

6) 385 7) 478 8) 496 9) 918 10) 863 - 63 - 37 - 385 - 504 - 813

V. Assignment

A. Find the difference.

1) 86 2) 59 3) 376 4) 937 5) 184 - 20 - 37 - 34 - 624 - 73

B. Subtract

1) 184 2) 85 3) 356 4) 897 5) 694 - 73 - 62 - 40 - 342 - 361

12

Subtracting 2- to 3- Digit Numbers with Regrouping in the Tens Place


Cognitive: Subtract 2- to 3- digit numbers from 2- to 3- digit numbers with regrouping in the tens place without or with zero difficulty

Psychomotor: Write the answers to the problem Affective: Practice courtesy


Skill: Subtracting 2- to 3- digit numbers from 2- to 3- digit numbers with regrouping in the tens place without or with zero

Reference: BEC PELC – I C1.3.1 Materials: flash cards – basic subtraction facts whose minuends are up to 18,

subtraction sentences, dialogue, games Value: Courtesy



1. Drill: Basic subtraction facts with minuends up to 18.

Ex.: 10 9 11 12 18 - 5 - 6 - 4 - 6 - 9

2. Mental Computation

a. Two or three pupils give simple problems on addition and subtraction for

the others to solve mentally.

b. Review - Let us check your homework in subtraction without regrouping.

86 49 399 258 - 52 - 27 - 208 - 126

3. Motivation

Dialogue: Mrs. Nuñez had just collected 45 Mathematics books from her pupils. After a while, Jason came to borrow 17 Mathematics books.

Jason: Good morning, Mrs. Nuñez. Mrs. Nuñez: Good morning. Anything I can do for you? Jason: May we borrow 17 Mathematics books? Mrs. Nuñez: Yes, you may. Mrs. Nuñez gives 17 Math books to Jason. Jason: Thank you, Ma‟am. Mrs. Nuñez: You‟re welcome.

*Valuing:

- What did Jason say to Mrs. Nuñez when he went to her to borrow books?

- What can you say about him? Is he a courteous boy? Why do you say so?

- How should we behave at all times?

13


1. Presentation

Present: A. 4 5 B. 7 0

- 1 7 - 5 6

- Look at the ones in A. Can you subtract 7 from 5? Why not? - Just like Jason who borrowed books from Mrs. Nuñez, 5 has to borrow

from 4. It can borrow one ten. - One ten plus 5 is what number?

Show where to place one ten:

- What happens to the 4 tens?

- Since a ten is taken from 4 tens,

4 tens will become 3 tens.

- Now subtract

(Do the same with subtraction sentence B)

2. Group Activities

Game: “Subtraction Relay”

Two teams with 3 members each to play at a time.

Each member to answer one particular digit of a subtraction sentence indicating regrouping.

A member goes to the board only upon the return of the 1st member

on the starting line.

The team who finishes first wins.

1

st member

2

nd member

3

rd member

Game: “Subtraction Relay”

Form two teams with 5 members each to play at the same time.

Each member has to answer a particular subtraction sentence.

All members go to the board when the teacher says “Go!”

They return to the starting line only when all the members have finished.

The team to return to the starting line first with correct answers wins.

3. Generalization How do we subtract numbers when the ones digit of the subtrahend is greater than the ones digit of the minuend?

4 7 2 - 1 5 6

1

4 15 - 1 7

3 1

4 15 - 1 7 2 8

14

C. Application Pupils answer some exercises in their papers/drill books.

a. Find the difference.

1) 625 2) 972 3) 493 4) 890 5) 492

- 518 - 358 - 156 - 386 - 173

b. If ( = 2), ( = + 1), and ( = + 4), find the difference of:

1) 2)

- -

IV. Evaluation

A. Find the difference of each item.

1) 170 2) 384 3) 473 4) 390 5) 971

- 139 - 218 - 164 - 263 - 752 B. Write the missing numerals to complete the difference.

1) 270 2) 282 3) 490 4) 891 5) 370

- 28 - 169 - 32 - 162 - 153 2___ __1__ __5__ 7___ __1__ V. Assignment Find the difference. 1) 791 2) 592 3) 864 4) 450 5) 370

- 483 - 383 - 719 - 36 - 143

6) 350 7) 681 8) 490 9) 642 10) 785 - 24 - 354 - 77 - 337 - 58

Subtracting 2- to 3- Digit Numbers with Regrouping in the Hundreds Place without or with Zero Difficulty


Cognitive: Subtract 2- to 3-digit numbers from 2- to 3-digit numbers with regrouping in the hundreds place without or with zero difficulty

Psychomotor: Write the answers to problems Affective: Show cooperation in group activities


Skill: Subtracting 2- to 3-digit numbers from 2- to 3-digit numbers with regrouping in the hundreds place without or with zero difficulty

Reference: BEC PELC I C 1.3.2 Materials: flash cards: subtraction facts, subtraction sentences with missing

parts, drill boards, place value chart, puzzle, activity cards Value: Cooperation

15



1. Drill a. 18 b. 13 c. 11 d. 14 e. 17 f. 12 g. 16

- 9 - 6 - 8 - 8 - 9 - 5 - 9

2. Review

Game: Where‟s My Missing Buddy? a. Distribute the flash cards with missing parts. b. Let the pupils look for their missing parts.

Example:

3. Motivation Picture of a boy riding in a jeep seated in front. Benjie lives far from the school. He takes a jeep in going to and from school. To keep himself busy, he writes down the plate numbers of 2 vehicles then he finds their difference. Once, he saw 2 nice cars. He wrote down their plate numbers: 709, 136. He tried to subtract one from the other. But he could not do it. He said to himself, „Our teacher has not taught us this yet.


1. Presentation

Ask: - What was Benjie‟s way of making himself busy while riding in a jeep? - What were the plate numbers which he failed to subtract?

Everybody, try finding the difference between 709 and 136. (If nobody can do it or if only a few know how to do it, explain) Present: 709

-136

a. Write the numbers in the place value chart.

Hundreds Tens Ones

7 0 9

- 1 3 6

b. Subtract the ones digit first. Since there are enough ones in the minuend, subtract. Then go to the tens. Since there are not enough tens in the minuend, tell the class to rename the tens digit. But there is no tens digit, so we go to the hundreds digit. Rename 7 hundreds as 6 hundreds and 10 tens.

Hundreds Tens Ones

67

10 0 9

- 1 3 6

3

36 - 14

975 – 253 = 753 722

22

16

c. We now have a tens digit in the minuend. Subtract the tens and the hundreds digits.

Hundreds Tens Ones

6 10 9

- 1 3 6

5 7 3

d. Present: 836

- 592 (Do the same for this subtraction sentence)

2. Group Activities

Activity 1 a. Work in groups of five. b. Distribute the activity cards to each group.

(To the teacher: Provide other activity cards for the other groups.)

Activity 2 a. Work in groups of five. b. Distribute the activity cards to each group.

(To the teacher: provide other activity cards for the other groups.) Activity 3 a. Work in groups of five. b. Distribute the activity sheets to the groups. ACTIVITY CARD # 3 Directions: Use your answers to fill in the puzzle. Subtract.

ACTIVITY CARD # 1 Direction: Find the difference. 208 407 635 916 - 57 - 95 - 83 - 52 907 505 852 729 -513 -141 - 682 - 466

ACTIVITY CARD # 2 Direction: Use the color code in giving the difference a. 309 b. 607 c. 709 d. 529 e. 417 - 49 - 32 - 51 - 74 - 53 f. 404 g. 929 h. 763 i. 807 - 254 - 594 - 382 - 294 Code: green – 658 yellow – 335 pink – 260

orange – 455 violet – 364 red – 513 white – 381 brown – 150 blue – 575

17

ACROSS: a. 309 c. 506 e. 513 f. 966 - 181 - 155 - 290 - 392 g. 654 h. 627 j. 906 - 392 - 495 - 651 DOWN: a. 229 b. 619 d. 607 e. 907 h. 918 - 198 - 531 - 455 - 663 - 663 *Valuing:

- Did you enjoy doing your group work? - Did you cooperate with one another? - Why is cooperation important in group work? - What should you remember when doing your group activities?

3. Generalization

How do we subtract numbers when the tens digit of the subtrahend is greater than the tens digit of the minuend?

C. Application

1. Solve and choose the correct answer by using a check mark (). a) 256 171 b) 671 581 c) 439 380 - 82 174 - 90 473 - 59 320 d) 908 898 e) 706 353 - 275 633 - 453 253 2. Give five subtraction sentences following the given rules:

The minuend and subtrahend are 3-digit numbers.

The ones digit in the minuend is greater than the subtrahend.

The tens digit in the minuend is zero. The tens digit in the subtrahend is greater than zero.

The hundreds digit in the minuend is greater than the subtrahend.

a

b

h i

j

e

d

f

g

c

18

IV. Evaluation

Subtract. 1) 347 2) 103 3) 764 4) 448 5) 306 - 56 - 93 - 392 - 155 - 144

V. Assignment Subtract. 1) 902 2) 759 3) 602 4) 527 5) 105 - 482 - 83 - 232 - 485 - 73 6) 836 7) 309 8) 636 9) 759 10) 909 - 574 - 19 - 591 - 86 - 615

Subtracting 2- to 3- Digit Numbers with Regrouping in the Tens and Hundreds Place without or with Zero Difficulty


Cognitive: Subtract 2- to 3- digit numbers from 2- to 3- digit numbers with

regrouping in the tens and hundreds place without or with zero difficulty

Psychomotor: 1. Write numbers in their respective place values 2. Write numbers legibly Affective: Obey the rules of the game


Skill: Subtracting 2- to 3- digit numbers from 2- to 3- digit numbers with

regrouping in the tens and hundreds place without or with zero difficulty

Reference: BEC-PELC I C 1.3.3 Materials: flash cards on subtraction, place value chart, activity cards, Tic-Tac-

Toe game board, strips of Manila paper Value: Obedience

III. Learning Experience


3. Drill

Subtract:

a. 12 b. 18 c. 11 d. 14 e. 15 f. 16 - 6 - 9 - 6 - 8 - 7 - 9

19

2. Review

- Which number has to be regrouped in a? - Where should it be regrouped? Why? - What is the answer in a? - Which number has to be regrouped in b? - Where should it be regrouped? Why? - What is the difference in b?

3. Motivation

a. Call on a pupil to pick a piece of paper in the red box. - Read and then write the number in the place value chart.

b. Call on another pupil to pick a piece of paper in the blue box. - Read and then write the number in the place value chart.


1. Presentation

* Let the pupils subtract the numbers in the place value chart. Example:

Subtract the ones digits first. Since there are not enough ones in the minuend, tell the class to rename the tens digit. But there is no tens digit, so we borrow from the hundreds digit. Rename 2 hundreds as 1 hundred and 10 tens.

H T O

1

2 10

0 4 7 9

We now have a tens digit in the minuend. Rename the tens digit as 9 tens and 10 ones. Then regroup 10 ones to make 14 ones.

H T O

1 9

0 10

4 7 9

a. H T O b. H T O

3 9 2 5 0 8 - 1 4 6 - 4 3

H T O

2 0 4 - 7 9

20

Subtract the ones, the tens and then the hundreds digits.

4. Group Activities

Activity 1 – “Super Tic-Tack-Toe”

600 - 348

820 - 289

404 - 265

700 - 488

868 - 769

946 - 773

900 - 643

500 - 278

901 - 239

905 - 288

601 - 472

720 - 191

Group the pupils by 3s. Only 2 pupils will play the game. The other pupil

holds the answer key. The one holding the answer key will tell if the answer of the player is right or wrong.

The two players share the same “Super Tic-Tack-Toe” game board. Each player has a set of 12 chips/markers of the same color. Make sure that the color of the chips between the two players is different.

Each player takes turn solving a problem on scratch paper before placing a marker on the square of the game board.

The players try to make as many tic-tac-toes as possible by aligning their markers horizontally, vertically or diagonally. The players also try to block each other from making a tic-tac-toe.

A marker may belong to more than one tic-tac-toe. The play continues until all squares are covered. The player with the most number of tic-tac-toes formed wins.

(Note: All winners stand before the class. They are given 5 bravo claps.) Activity 2

Divide the class into 5 groups. Distribute an activity card to each group.

Activity Card

Directions: Solve. Write your computation in 4

1

sheet of manila paper. 1. The boys gathered 510 empty soft drinks cans. They

gave 235 to their friends. How many soft drinks cans were left?

2. The Grade II pupils made 400 pencil holders from tin cans. They sold 265 pencil holders. How many were left?

3. Mang Tomas picked 370 ripe mangoes. He gave 86 mangoes to his friends. How many mangoes were left?

4. Mr. Melo takes care of 375 cows and goats. If there are

H T O

1 9 14 7 9

1 2 5

21

188 goats, how many cows are there? 5. Last year, there are three hundred twelve birds in the bird

sanctuary. This year, one hundred thirty-eight birds are released in the forest, how many birds were left in the bird sanctuary?

The group who gets the most number of correct answers in 5 minutes wins.

Activity 3

Game: “Palosebo” Mechanics: Divide the class into at least 5 groups Teacher draws or makes the “palosebo” on strips of manila paper or

cartolina for each group as shown below. Teacher gives a set of subtraction problems for each group. The groups solve the given subtraction problems for 3 minutes. The groups write their answers on the “palosebo”. The group with the most number of correct answers win.

* Valuing:

- Did the players stop when the time was up? - What kind of players are they? Did they obey the rules? - As players, what should we do with the rules of the games?

3. Generalization

How do we subtract numbers when the tens and ones digits of the subtrahend are greater than the tens and ones digits of the minuend?

C. Application

a. Subtract. Write the answers in your paper.

1) 252 2) 801 3) 450 4) 836 5) 900

- 87 - 596 - 84 - 387 - 458

b. Fill in the blanks with numbers to make each sentence true. 1) Use 1, 2, 4, and 5 2) Use 0, 4, 5, and 7

_ _ _ _ _ _ - _ _ _ - _ _ _

8 7 2 7 5

22

IV. Evaluation

Subtract. Write the answers in your notebook.

1) 72 2) 400 3) 76 4) 509 5) 780 - 36 - 185 - 57 - 184 - 464

6) 384 7) 407 8) 23 9) 649 10) 123 - 59 - 245 - 17 - 83 - 98

V. Assignment

Subtract the following. Don‟t forget to regroup.

1) 351 2) 200 3) 425 4) 302 5) 900

- 186 - 93 - 86 - 87 - 496

6) 873 7) 704 8) 658 9) 522 10) 840 - 94 - 548 - 79 - 377 - 91

Using Addition to Check Subtraction


Cognitive: Use addition to check subtraction Psychomotor: Write numbers correctly Affective: Practice sharing with others


Skill: Addition to check subtraction Reference: BEC-PELC I.C.2

Materials: pebbles/stones, shells, flash cards with subtraction facts Value: Sharing



1. Drill

Subtraction Facts

a. 18 b. 12 c. 13 d. 11 e. 15 f. 14

- 9 - 6 - 5 - 7 - 9 - 8

2. Review

Add the following:

a. 35 b. 25 c. 21 d. 17 e. 26 + 18 + 10 + 7 + 9 + 13

23

5. Motivation I have shells on the table. Come and get one and answer the addition and subtraction sentence written on it. Use them to answer the following number sentences Example: 2 + 4 = , 6 – 4 = , 5 + 4 = , 9 – 5 = ,

etc.

B. Developmental Activity

1. Presentation

I have stones on the table. Count the stones. How many stones are there? (56) Remove 12 from them. How many were left?

a. Write the subtraction sentence for the problem presented. (56– 12 = 44) b. Ask: What is the subtrahend? (12) c. What is the minuend? (56) What is the difference? (44) d. Ask pupils to check the answer by adding the difference and the

subtrahend.

Ask: - What is the difference? (44) - What is the subtrahend? (12) - What is the sum of the difference and the subtrahend when

added? (56)

e. Write the addition sentence: 44 + 12 = 56 f. Show to the class the subtraction sentence and the addition sentence.

Through arrows show the corresponding parts of the two sentences.

minuend 56 44 addend subtrahend - 12 + 12 addend difference 44 56 sum

g. Using the above illustration, show/teach the children how they will check

the subtraction sentence.

2. Group Activities

Activity 1 (To be given to slow learners) Subtract then check: a. 74 b. 84 c. 92 d. 25 e. 65

- 50 - 43 - 51 - 23 - 35

Subtract then check (To be given to fast learners) a. 285 b. 369 c. 926 d. 245 e. 780

- 152 - 248 - 701 - 124 - 360

Activity 2 Game: Divide the class into 4 groups. Have them answer the exercises with speed and accuracy. The group with more correct answers wins.

24

Subtract the following then check by adding.

a. 630 b. 704 c. 462 d. 537 - 275 - 385 - 314 - 242

Activity 3

Solve the word problem then check your answer.

Josh donated 59 Science and Mathematics books for the barangay‟s mini library. If there are 32 Mathematics books, how many Science books were there?

*Valuing:

- Going back to the problem above, who donated the books? What character trait does Josh show? Why is it important to practice sharing with others?

3. Generalization

How do we check our answers to subtraction exercises?

C. Application

1. Subtract then check.

a. 85 b. 50 c. 75 d. 81 e. 34

- 39 - 24 - 59 - 48 - 27 f. 356 g. 428 h. 780 i. 453 j. 505 - 178 - 364 - 469 - 315 - 208

2. Complete each so that the sum of the two numbers on the opposite circles is

the number in the rectangle.

IV. Evaluation

Subtract then check.

a. 73 b. 81 c. 53 d. 80 e. 64

- 26 - 37 - 15 - 69 - 28

f. 548 g. 702 h. 243 i. 543 j. 862 - 319 - 128 - 170 - 197 - 315

248

356

425 179

a. b.

415

289 504

c. 192

627

386

25

V. Assignment

Subtract then check.

a. 98 b. 526 c. 642 d. 354 e. 657

- 52 - 215 - 349 - 166 - 359

Subtracting Mentally


Cognitive: Subtract mentally 1-digit number from 1- and 2-digit numbers with minuends up to 50 without regrouping

Psychomotor: Solve mentally 1-digit number from 1- and 2-digit numbers with minuends up to 50 without regrouping

Affective: Show love for parents II. Learning Content

Skill: Subtracting mentally 1-digit number from 1- and 2-digit numbers with minuends up to 50 without regrouping

Reference: BEC PELC I C 3 Materials: Drill cards with basic subtraction facts, hand puppet of a magician,

bingo cards, drill cards, Example: 46 38 - 3 - 6 Value: Love for parents



1. Drill

Relay Drill cards with basic subtraction facts 9 6 8 7 9 - 3 - 2 - 5 - 4 - 5

2. Review

Subtract. Then check your answers by adding the difference and subtrahend to get the minuend. a. 63 b. 91 c. 56 d. 349 e. 427 - 38 - 45 - 17 - 86 - 145

3. Motivation

Show the picture of a hand puppet of a magician.

26

Ask: Have you seen a magician? What does a magician do? Would you like to see how a magician performs some tricks?


1. Presentation

A magician placed 24 rabbits in a hat and subtracted them by a mystery number. Only 9 of the rabbits came out. What is the mystery number? a. How many rabbits did the magician have? b. How many rabbits came out of the hat? c. What is the mystery number? d. What did you do to get the mystery number?

2. Group Activities

Activity 1 Bingo Game a. Divide the class into groups of five. b. Distribute bingo cards for each group. c. Look at the cards as the teacher flashes them.

Example: 45 48 37 26 19 - 5 - 7 - 5 - 3 - 7

d. Mark with a stone the correct number that answers the number combination given by the teacher.

e. The first group to come up with the correct pattern wins the game.

B I N G O

13 25 29 32 40

10 22 26 30 43

12 24 28 34 42

14 21 27 36 41

Activity 2

Pair-shared Activity a. Listen carefully as the teacher dictates the word problem. b. The first pair to guess the correct answer will stand up.

1) What number is 29 less 8? 2) What is the difference between 48 and 6? 3) Subtract 5 from 37. 4) What is 49 decreased by 6? 5) Take away 2 from 27.

3. Generalization

How do you subtract numbers mentally?

C. Application

Teresa earned 28 in selling banana cues. She spent 6 and gave her mother the rest. How much did her mother receive? Ask: How much did Teresa earn in selling banana cues? How much did she give her mother? What trait does Teresa show?

27

If you would earn money, would you do the same? How do you show love for your parents?

IV. Evaluation

1. Subtract mentally. (The teacher will flash the cards given below.) 27 39 50 48 36 - 5 - 6 - 10 - 3 - 4

2. Subtract mentally.

(The teacher will dictate the word problems below) a. What number is 28 less 5? b. What is the difference between 4 and 37? c. What is 49 decreased by 7? d. What is 38 minus 6? e. What is 3 subtracted from 15?

V. Assignment

Subtract mentally. 1. What is the difference between 6 and 48? 2. What is 37 decreased by 5? 3. What is 24 less 4? 4. What is 2 subtracted from 35? 5. What is 43 minus 3?

Analyzing 1 step Word Problems Involving Subtraction (What is Asked, What is/are Given, Word Clues and Operation to be Used)


Cognitive: Tell what is asked, what is/are given, word clues and operation to be used in word problems involving subtraction

Psychomotor: Write what is asked, given, word clues and operation to be used Affective: Find pleasure in reading


Skill: Telling what is asked, given, word clues and operation to be used in word problems involving subtraction

Reference: BEC PELC I C 4.1.1.1 Materials: word problems written on manila paper, chart, activity cards, drill

boards or show cards, flash cards, pocket charts Value: Enjoyment in reading



1. Drill

Use flash cards of subtraction facts. Subtract mentally. a. 35 b. 26 c. 45 d. 19 e. 50 - 3 - 6 - 4 - 6 - 30

28

f. 29 g. 36 h. 45 i. 29 j. 48 - 9 - 3 - 5 - 7 - 5

2. Review

Solving subtraction problems and comprehension check-up a. Tony needed 220 popsicle sticks for his project. He had 100 sticks and

his friend gave him 50 sticks. How many more sticks will he need? Ask: Who needed popsicle sticks? How many popsicle sticks does he have? How many popsicle sticks did his friend give him?

How many more sticks does he need? b. Daniel bought a book for 92. How much change did he get from

100? Ask: Who bought a book? How much is the cost of the book? How much was his money? How much change did he get?

3. Motivation

Talk about going on a field trip. Ask: Have you joined a field trip? Where did you go? What did you bring along? Did you have fun? Why?


1. Presentation

Teacher tells a story. In a field trip, the children bought 165 tetra packs of juice. If 86

packs were consumed, how many packs were left?

Tell the class: Let us analyze the problem. First, we need to know what is asked in the problem. - What is asked? (number of tetra packs left) - What are the given facts? (165 tetra packs from the children) - What is the word clue (left) - What are the operations to be used? (subtraction)

2. Group Activities

Have the pupils solve the problems in groups. Form 6 groups and distribute one activity card for each group. Tell the pupils to solve the problem following the steps discussed.

Activity Card 1

The Boy Scouts went camping. They gathered 75 pieces of firewood. They used 50 pieces for cooking and for a bonfire. How many pieces of firewood were left? Activity Card 2

Mrs. Santos went to the market. She spent 265 for meat and vegetables. If she had 500, how much money was left for her? Activity Card 3

Among the 480 Grade two pupils, 381 joined the Field Day. How many pupils did not join?

29

Activity Card 4 There were 104 boys and girls who attended the Field Day. If 45

came in costumes, how many did not come in costumes? Activity Card 5

Conrad had a deposit of 580 in the bank. He withdrew 250 to buy a gift for his mother. How much money was left in his deposit? Activity Card 6

There are 226 Grade two children in Rizal Elementary School. There are 118 girls. How many are boys?

Ask the leader of the group to read the problem and a member to write the answer on the blackboard or on a sheet of manila paper. Check for the accuracy of the answers.

*Valuing:

- Did you enjoy reading the activity sheet assigned to your group? Why? Is it good to love reading? Why? (Because we will know many things by reading)

- 3. Generalization

How do we analyze word problems?

C. Application

1) Read and analyze the word problems below following the given steps. a. What is asked? b. What are the given facts? c. What is the word clue? d. What is the operation to be used?

1. Mang Berto brought 350 coconuts to the market. If he sold 198 coconuts,

how many coconuts were not sold? 2. There were 400 mango and santol trees in Mang Rogel‟s farm. If 153

were mango trees, how many were santol trees? 3. Mother asked Clara to buy a dozen eggs in the nearby store. How much

was left of her 100? 2) Supply the missing information.

1. There are 300 Math books in the library. There are also 256 Science books.

2. Andrea saved 255 from her daily allowance. How much is her change if she bought a new bag?

3. Twenty-eight boy scouts from an elementary school attended the camping. How many more girl scouts than boy scouts attended the camping?

IV. Evaluation Analyze each of the problems using the following steps:

a. What is the problem about? b. What are the given facts? c. What is the word clue? d. What is the operation to be used?

1. Mang Celso has 250 boiled corns to sell. He sold 125 pieces in the morning. How

many more boiled corns will he still sell in the afternoon?

30

2. There were 323 pupils in Grade Two. Only 145 joined the food sale. How many pupils did not join?

3. The children prepared 500 cookies for sale. They sold 380 cookies. How many cookies were not sold?

V. Assignment

Copy and solve the problem. Answer the following questions.

Lourdes earned 315 points for the raffle. But she needs 500 points to be able to join the grand raffle. How many more points does she need? 1. What is asked? 2. What are the given facts? 3. What is the word clue? 4. What is the operation to be used?

Analyzing Word Problems Involving Subtraction (Transforming Word

Problems into Number Sentences and Stating the Complete Answer)


Cognitive: 1. Transform a word problem into a number sentence involving subtraction 2. Use the correct operation 3. State the complete answer

Psychomotor: Write the number sentence, operation being used and the complete answer

Affective: Practice being thrifty II. Learning Content

Skill: Transforming word problems involving addition into number sentences, using the correct operation and stating the complete answer

Reference: BEC PELC I.C.4.1.2 – 4.1.4 Materials: Chart with Word Problems Flash cards of subtraction facts Value: Thrift



1. Drill

Subtraction facts a. 18 b. 12 c. 13 d. 11 e. 15 f. 14 g. 17

- 9 - 6 - 6 - 7 - 9 - 5 - 9

h. 12 i. 16 j. 18 k. 14 l. 13 m. 16 - 4 - 9 - 9 - 5 - 6 - 8

2. Review

a. Match the step with the things to do in a particular 4-step method of solving problem. Divide the class into two groups. The fastest group that can match correctly wins the game.

31

b. Give the correct answer to the problem (Pupils may use show-me-

boards.) 1. There were 10 birds on a tree. Six flew away. How many were

left? 2. Beth drew 15 circles. She colored 8 circles red and the other

green. How many circles were green? 3. Father brought home 11 durian candies. His son ate 5 durian

candies. How many were left?

3. Motivation

Ask the pupils if they have some savings. Ask them why they save money.


1. Presentation

Present the word problem below.

Teacher explains and shows how to transform a step word problem into a number sentence. Let the pupils solve the problem. Guide the pupils in writing and solving the problem in two ways, horizontal and vertical solutions. Let them also label their answer correctly.

20 – 5 = N 20 – 5 = 15 amount of money Arnold puts and saves

in his coconut shell bank

or 20 – 5 15 amount of money Arnold puts and saves in his

coconut shell bank

Provide another problem to solve.

UNDERSTAND

LOOK BACK

DO

PLAN

Review and answer with label

Give the given facts

Identify the equation

Write the equation and answer the problem.

Arnold has a coconut shell bank. Everyday he receives 20 from his mother. He only buys a sandwich for recess at 5 and the rest of the money is saved. How much does he put in his coconut shell bank?

Lani invited her classmates to her birthday party. Forty of her classmates came. When evening came, 12 of her classmates went home. How many were were left in the party?

32

Guide the pupils in analyzing the word problem. - What is asked in the word problem? - What will you do to find the number of Lani‟s classmates that were left in

the party? - Why will you subtract? What is the word clue for subtraction? (left) - What is the correct number sentence?

Call some pupils to show their solutions on the problem and stating the answer with the correct label on the board. Let them explain their solutions and answers. Guide the pupils to identify/choose the correct solution and answer in case some of the pupils gave wrong answers. Guide them also in explaining why their solutions are wrong.

40 classmates - 12 classmates went home 28 classmates were left

2. Group Activities

Divide the pupils into 5 groups.

Let each group discuss two word problems given below.

Let them analyze the problems using the steps already learned to come up with the appropriate number sentences.

Let them solve the problem and label the answer correctly.

Share the groups‟ ideas/answers to the class.

a. You and your brother opened your piggy bank to buy a gift for your mother. You were able to save 53 and your brother saved 67. How much more is your brother‟s savings than yours?

b. The fisherman caught 546 fishes. He sold 392 of them. How many were left for his family?

c. Praxedes is 54 years old. Vicky is 49 years old. How many years older is Praxedes than Vicky?

d. Marites had 500. She bought a pair of shoes for 299. How much money had she left?

e. The dress is 50 less than its original price which is 395. What is the new price of the dress?

f. There are 949 pupils in Malinta Elementary School while in Hulugan Elementary School there are 468 pupils. What is their difference?

g. There were 492 Cub Scouts, 256 joined the parade. How many Cub Scouts did not join the parade?

h. Rose has 100. She bought a bag for 99. How much was her change?

i. Mother bought 148 eggs. She used 125 eggs in her leche flan. How many eggs were left?

j. Mr. Luis earned 650 from driving a taxi. He gave 500 to his wife. How much money had he left?

3. Generalization

How did we transform/change the word problems into number sentences? Why do we need to transform word problems into number sentences?

What are the steps in solving word problems involving subtraction?

33

C. Application

Change the following word problems into number sentences. Solve then label the answer correctly.

1. Joshua‟s money is 15. He bought chocolate cookies for 8 and saved the

rest. How much did he save? 2. Ana had 36 roses. She gave 20 of them to her teacher and friends. How

many roses were left? 3. Linda spent half of her money in a store. She spent half of the money that

remained in a second store. She had 15 left in her wallet. How much money had she at first?

IV. Evaluation

Read the word problems carefully. Then answer the questions that follow.

1. Danilo earned 485. Edgar earned 450. How much more did Danilo earn

than Edgar? What is the correct number sentence? ___________ What is the complete answer? _____________

2. In a 35-item test, Fred made 9 mistakes. How many correct answers did he get? What is the correct number sentence? ___________ What is the complete answer? _____________

3. Nena‟s mother is a seller. She had 650 bananas to sell. She had sold 298

bananas in the morning. How many would she sell in the afternoon? What is the correct number sentence? ___________ What is the complete answer? _____________

4. Luis had 35. He bought a pencil and pad paper which cost 18. He saved the rest of his money. How much did he save?

What is the correct number sentence? ___________ What is the complete answer? _____________

5. A farmer planted 125 calamansi seedlings. After a month, 46 died. How many were left?

What is the correct number sentence? ___________ What is the complete answer? _____________

V. Assignment

Transform each problem into a number sentence and solve and give the complete answer. 1. In a school of 698 grade two pupils, 264 are girls. How many are boys? 2. Ruben has a weekly allowance of 350. He spent 50 for his project. How

much money was left to him? 3. Agnes collected 182 foreign stamps. He gave 96 to his friends. How many

stamps were left to her?

34

4. In the Clean and Green Campaign, 101 Grade II pupils joined the drive. There were 48 pupils from Section Sampaguita. How many pupils were from Section Rosal?

5. Amad gathered 112 coconuts for sale. He sold 98 pieces. How many were left?

Analyzing 2 step Word Problems Involving Addition and Subtraction (Telling what is Asked, Given, Word Clues, Hidden Question, and

Operation to be Used)


Cognitive: Tell what is asked, what are given, the word clue/s, hidden question and the operation to be used in word problems involving addition and subtraction

Psychomotor: Write what is asked, given, word clue/s, hidden question and operation to be used

Affective: Give the importance of being industrious II. Learning Content

Skill: Telling what is asked, what are given, the word clue/s, hidden question and the operation to be used in word problems involving addition and subtraction

Reference: BEC PELC I.C.5.1.1.1 Materials: Problems in chart Value: Industry



1. Drill - Add and subtract one digit numbers.

Ex. 9 + 1 – 5 = n 7 + 3 – 4 = n 6 + 5 – 3 = n

2. Review Perform the indicated operation:

a) 85 b) 98 c) 417 d) 542.45 e) 834

- 52 + 69 - 237 + 217.30 - 498

3. Motivation

Ask the pupils, “What is your father‟s occupation?” Show a picture of a fisherman catching fish. Ask the pupils the importance of fisherman in the community/country.

35


1. Presentation

Present this story problem.

Guide the pupils in analyzing the word problem. What is asked in the problem? total kilograms of tilapia left

What are given? 67 kilos of tilapia to be sold, 5 kilos sold in the morning, 2 kilos sold in the afternoon and 3 kilos gave to his neighbors

What is the hidden question? What is the total kilograms of tilapia sold and given?

How many operations will you use in solving the problem? Two

What are they? Addition and subtraction

What word clue/s helps you identify the operations to be used in solving the problem? And – for addition; Left – for subtraction

2. Group Activities

Group the pupils into four. Give each group a problem to analyze following the steps given.

What is asked in the problem?

What are given?

What is the hidden question?

What are the word clue/s to help you identify the operations to be used in solving the problem?

What are the operations to be used? Group I

Nilo is taking care of 286 chickens in his poultry. He sells 96 in January and 40 in February. How many chickens were left? Group II

Edwin is an industrious boy. He sells doughnuts to earn money. He has 120 doughnuts to sell. He sold 25 doughnuts in the morning and 15 doughnuts in the afternoon. How many doughnuts does he still have to sell? Group III

Bernie earns money by selling newspapers. In a day, he earns 62 pesos. He buys a kilo of sugar for 27 pesos and a pack of coffee for 19 pesos. How much money was left to him? Group IV

Aling Rosa earns money by selling sampaguita. In a day, she earns

70. Everyday, she spends 22 for a kilo of rice and 40 for a half kilo of galunggong. How much is left of her daily earnings? *Valuing:

- From the problems discussed, what character trait do you see in each person? What is the importance of being industrious? Who among you here are industrious?

- Now, let‟s go back to the problem. How did you come up with your answer? Did you follow the steps in analyzing a 2-step word problem? (Pupils will explain their answer)

Mang Juan is a fish vendor. He has 67 kilos of tilapia to sell. He sold 5 kilos in the morning, 2 kilos in the afternoon and gave 3 kilos to his neighbors. How many kilos were left to him?

36

3. Generalization

What are the steps in analyzing a 2-step word problem involving addition and subtraction including money?

C. Application

a. Analyze the problems following the steps learned.

1. May wants to buy a pack of biscuits costing 5 and a glass of juice for

2. She has only 5. How much more money does she need? 2. Claire is having a party for 35 friends. She sends 11 invitations in the

morning and 9 invitations in the afternoon. How many invitations does she still have to send?

3. My father planted 68 pechay seedlings and 137 potato seedlings. After two months, 18 seedlings died. How many seedlings were left?

b. Create a word problem using the following facts involving addition and

subtraction.

1. 500, 2 shirts, 250 2. 684 canned goods, 185 families from Barangay A, 263 families from

Barangay B

IV. Evaluation

Read the word problems carefully. Then answer the questions below.

1. Eloisa bought 80 worth of bananas and 156 worth of mangoes. How much change did she receive from a 500-peso bill? a. What is asked? _____ b. What are given? _____ c. What is/are the word clues? d. What is the hidden question? _____ e. What are the operations to be used? _____

2. A tray contained 125 cookie bags for recess. Of these cookie bags, 75 were sold

to the grade two classes and 40 were sold to the grade one classes. How many cookie bags were not sold? a. What is asked? _____ b. What are given? _____ c. What is/are the word clues? d. What is the hidden question? _____ e. What are the operations to be used? _____

V. Assignment

Answer the questions after the word problem.

1. Mr. Reyes made a total sale of 750 for unripe mangoes and 285 for ripe

mangoes. He gave 600 of his sales to his wife and kept the rest. How much did he keep? a. What is asked? b. What are given? c. What is/are the word clues? d. What is the hidden question? e. What are the operations to be used?

37

2. There are 48 visitors at a party. Some are parents, teachers and children. There are 18 parents and 12 teachers. How many children are in the party? a. What is asked? b. What are given? c. What is/are the word clues? d. What is the hidden question? e. What are the operations to be used?

Analyzing Word Problems Involving Addition and Subtraction (Transforming Word Problems into Number Sentences and Stating the Complete Answer)


Cognitive: 1. Transform a word problem into a number sentence involving addition and subtraction

2. Use the correct operation 3. State the complete answer

Psychomotor: 1. Write word problems into number sentences, use the correct operation and state the complete answer

Affective: Practice being thrifty at all times


Skills: Transforming word problems involving addition and subtraction and stating the complete answer

Reference: BEC PELC I C 5.1.2 – 5.1.4 Materials: flash cards, charts, pictures Value: Thrift



1. Drill

Addition and subtraction facts in flash cards a. 43 b. 32 c. 132 d. 96 e. 276 f. 83 g. 65

+ 54 + 46 + 305 - 45 - 165 - 12 - 23

2. Review Read the word problems and answer the questions that follow.

a. Mary has 250. She bought a bag and an umbrella worth 125. How much money was left? 1) What is asked? _____ 2) What are given? _____ 3) What is the word clue? _____ 4) What is the hidden question? _____ 5) What is the operation to be used? _____

b. Alex has 100. His brother has 75.00. How much money do they have together? 1) What is asked? _____ 2) What are given? _____ 3) What is the word clue? _____ 4) What is the hidden question? _____ 5) What is the operation to be used? _____

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Solve the word problems. a. At one roadside, there were 25 cars parked. At another roadside, there

were 16 cars. How many cars were there in all? b. There were 410 boxes. Train workers loaded 20 boxes. How many boxes

were left?

3. Motivation

Do you have money today? How much money do you have? Will you spend all? What will you do?


1. Presentation

a. Let us have a skit “The Family”. Who are the members of the family? Who would like to play the role of the Mother? Father? Alvin?

Alvin: I‟m going to school, mother.

Mother: Here is your money. (Mother gives him 15.)

Father: I will also give you 10 because you helped me in the farm. Alvin: Thank you, father, mother.

Alvin got 25. In school, he spent 12 only and saved the rest. How much money was left to him?

What is asked in the problem?

What facts are given?

What is the word clue?

So, what is the hidden question?

What is the operation to be used in answering the problem?

Can you now write a number sentence to the problem? Let them discuss this idea by pairs. Then call some pupils to show their number sentences on the board. Guide them to

identify the appropriate number sentence. ( 15 + 10) – 12 = N)

How can you solve the problem using the number sentence? Let the pupils explore possibilities in solving the problem.

What is the correct label to the answer?

What are the steps we used in analyzing this problem? *Valuing:

- What can you say about Alvin? - Is it good to save money? - What character trait did he show?

b. Show another problem (Show a mango tree and cutouts of birds.) While reading the problem, pupils put the cutouts of birds on the mango tree. Problem: There were 36 birds in a tree. Twenty-two more came but 15 birds flew away. How many birds are there now?

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Call some pupils to give the number sentence for the problem. Guide the pupils to identify the appropriate number sentence. Let them also identify the word clues for each operation used. (36 + 22) – 15 = N Guide also the pupils in solving for the correct answer. Let them label their answers correctly.

2. Group Activities

Divide the class into 3 groups. Give each group two or three problems. Let them answer the following.

What is the number sentence?

What is the complete answer? After the groups solved the problems, let them present their solutions to the class. Examples:

b. Dino had 700. He spent 235 for clothes and saved 200 in the bank. How much does Dino have now?

c. The government was giving out 3 585 tree seedlings. Eight hundred thirty-five were given to one barangay and 788 to another barangay. How many seedlings were left for the other barangays?

d. Mario gathered 146 guavas in the morning. In the afternoon, he gathered 65 guavas. If mother sold 158 of them, how many guavas were not sold?

e. Lito earned 250 for selling newspapers and 275 for selling

magazines. He spent 245 for his food. How much money was left for his savings?

f. Mother bought a polo shirt worth 215 and a shirt for 125. If she

gave 500.00 to the cashier, how much was her change?

3. Generalization

How do we transform word problems involving addition and subtraction into a number sentence? What are the steps in solving word problems involving addition and subtraction?

C. Application

Read the problems carefully. Then answer the questions that follow.

Rita earns money by selling sampaguita. In a day, she earns 100. Everyday,

she spends 24 for a kilo of rice and 28 for a kilo of sugar. How much is left of her daily earnings?


What is the complete answer? Lito has two boxes of marbles. There are 425 marbles in one box and 355 in

another box. Of these, 540 are red marbles. How many marbles are of other colors?


What is the complete answer? _____

Which Book? A class in Grade II sold their old books to raise money to help the victims of

typhoon. Carlos helped by buying 3 books. If he had 100 for 3 books, which of the books below can he buy? Why?

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IV. Evaluation

Write the number sentence then solve for the correct answer. Label the answer correctly.

1. Bernie loves pets. He has 55 pigeons in a big cage and 20 in another. His mother said he could only keep 35 pigeons. How many pigeons must he sell? Number sentence: __________

2. Mang Lito sells doughnuts. He had 585 doughnuts to sell. He sold 125 doughnuts in the morning and 200 in the afternoon. How many doughnuts does he still have to sell? Number sentence: __________

3. A housing investor was able to build 5 200 new houses. Of these, 1 350 were in Laguna, 2 100 in Bulacan and the rest in Cavite. How many new houses were built in Cavite? Number sentence: __________

4. Riza bought 125 sheets of bond paper for her project yesterday. She bought 85 more but gave 55 sheets to Nida. How many sheets of bond paper does she have now? Number sentence: __________

5. Mr. Santos harvested 745 sacks of palay last year. This year, he harvested 825 sacks of palay. If he sold 1 200 sacks, how many sacks of palay remained for his family? Number sentence: __________

V. Assignment

Solve the following word problems following the steps in problem solving.

1. Mr. Fulgencio hired 945 workers in his factory. Last month, he hired 250 more. Of these, 850 are females, how many are male workers in the factory?

2. Rosie made 450 butter cookies. She also made 350 vanilla cookies. She sold 650 cookies to her friends and neighbors. How many cookies were left to her family?

3. Mang Paul planted 225 coconut seedlings in his farm. After a month, he planted 215 more. He found out that 105 coconut seedlings did not grow. How many plants grew?

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In Elementary Mathematics Grade 2