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Adding Three 1-digit Numbers Having Sums Up to 18

I. Learning Objectives

Cognitive: Add three 1-digit numbers having sums up to 18 horizontally andvertically

Psychomotor: Write the addends and discover the Magic Sums

Affective: Show accuracy in adding numbers

II. Learning Content

Skill: Adding three 1-digit numbers having sums up to 18

Reference: BEC PELC I B. 1.6

Materials: roulette, real objects, counters, number cards (0-18) T. 13-16picture cards, cutouts of animals

Value: Accuracy

III. Learning Experiences

A. Preparatory Activities

1. Drill

Spin the outer circle of the roulette

and give the sum.

2. Review

The pupils will write 2 addition stories for every domino card to be presented usingtheir show-me-boards.

Example: 3 + 4 = or 4 + 3 =

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3. Motivation

Children, have you been to the zoo? What animals did you see there? Can you countthem at the same time? Let us discover an easy way to count them.

B. Developmental Activities

1. Presentation

a. Present a word problem using cutouts of animals.

The children went to the zoo. They saw 5 birds, 4 monkeys and 3 lions. How many

animals did they see in all?Who went ot the zoo?

What did they see?

Can you help me count the animals they saw using the easy way?

How many birds did they see? Monkeys? Lions?What will be the addition sentence?

Write below the cutouts: 5 + 4 + 3 =

How many addends are there? Lets add them horizntally.What should we add first to get its sum? (The first 2 addends)

Show: (5 + 4) + 3

9What do we do next? (Add its sum to the last addend to find the total sum.)

Show: (5 + 4) + 3

9 + 3 = 12

What is the other way of writing addition sentences?Write it vertically.

What should we add first?

Show: 5 94

+ 3 > + 3

12

Do we follow the same step in finding the sum horizontally?

What should we remember in finding the sum of three 1-digit numbers? (Add first thetwo addends and add its sum to the last addend)

What should we remember to get the correct answer? (Be careful in adding numbers)

b. Pupils will write addition sentences for each picture story shown by the teacher usingshow-me-boards. Follow the steps in finding the sum of three addends.

Example:

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(1 + 3) + 6

4 + 6 = 10

c. Draw this on the board and say - the sum of 3 numbers in each column is equal to thesum of 3 numbers in each row. Children needs to discuss the Magic Sum

(From p. 96, Math for Everyday Use)

*Valuing: How were you able to give the correct answer? Why? (When we do our work

well we give accurate/correct answer)

2. Generalization

How do we add three 1-digit number? We add the first 2 numbers then add its sum to thethird number.

How did we add the numbers? (Accurately.)

C. Application

Addition contestCall three pupils to go to the board. Give one number sentence with 3 addends. The first one

to asnwer it correctly wins the game.

Repeat until most of the pupils have participated.

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Who won the game?

What did you feel?

Is is good to show others what we know?

IV. Evaluation

A. Give the sum:

3 + 4 + 2 = 2 + 9 + 3 =

7 + 1 + 3 = 8 + 1 +6 =

4 + 8 + 1 = 2 + 3 + 8 =

B. Choose the correct answer in the box then encircle that number.

Example:

C. Complete the box wherein 3 columns is equal to the sum of 3 numbers in each row.

Example:

V. Assignment

Participate addition of three 1-digit numbers with sums up to 18.

3 + 8 + 7 = 8 + 4 + 2 =

9 + 8 + 1 = 5 + 7 + 5 =4 + 3 + 6 =