Topicm0a42d0528af2970f_1528449000663_0Topic

Addition of the integers

Levelm0a42d0528af2970f_1528449084556_0Level

Second

Core curriculumm0a42d0528af2970f_1528449076687_0Core curriculum

III. The integers. The student:

2) interprets the integers on a number line,

5) does simple mental calculations of integers.

Timingm0a42d0528af2970f_1528449068082_0Timing

45 minutes

General objectivem0a42d0528af2970f_1528449523725_0General objective

Doing the simple operations of mental calculation or more difficult ones in writing and using these abilities in practical situations.

Specific objectivesm0a42d0528af2970f_1528449552113_0Specific objectives

1. Addition of the integersaddition of the integersAddition of the integers.

2. Using the associative and commutative properties of addition.

3. Communicating in English; developing mathematical and basic scientific, technical and digital competences; developing learning skills.

Learning outcomesm0a42d0528af2970f_1528450430307_0Learning outcomes

The student:

- adds the integers, interprets the integers on the number line,

- specifies the sign of the integers.

Methodsm0a42d0528af2970f_1528449534267_0Methods

1. Learning game.

2. Situational analysis.

Forms of workm0a42d0528af2970f_1528449514617_0Forms of work

1. Individual work.

2. Group work.

Lesson stages

Introductionm0a42d0528af2970f_1528450127855_0Introduction

The students brings the cards with the numbers which they have prepared at home:

- – 6, -5, -4, -3, -2, -1 – yellow cards,

- 1,2,3,4,5,6 – red cards,

- 0 – green card.

Teacher introduces the topic of the lesson: the addition of the integersaddition of the integersaddition of the integers.

Revision of the notion of the absolute value.

Procedurem0a42d0528af2970f_1528446435040_0Procedure

[Slideshow]

The students work individually using their computers. They are going to find out how  to add the integers.

Students work in pairs. They use the cards they have prepared before.

Each of players draws two cards and adds the numbers written on them. The winner is the person who gets the larger sum. They repeat the activity for few times and check their results by using the calculators.

Discussion: What does the sign of the sum of two integers depend on?

The students should come up with the following conclusions:

- The sum of two negative integers is the negative numbernegative numbernegative number.
- The sum of two positive integers is the positive numberpositive numberpositive number.
- The sum of the opposite number equals zero.
- The sum of the positive and negative numbernegative numbernegative number is negative if the absolute value of the negative is larger than absolute value of the positive.

The students use their skills to complete the following tasks.

Task 1

Specify the sign of the sum without doing any calculations.m0a42d0528af2970f_1527752256679_0Specify the sign of the sum without doing any calculations.

a) ( - 2456) + 67

b) (- 876) + 943

c) (- 345) + 6578

d) 123 + (- 32)

Task 2

Find the number larger by 8 of the following numbers:

- 1, - 5, - 6, - 8, -15.

Task 3

Add the number – 14 and the following numbers:

- 3, - 12, 6, 30, - 6.

Task 4

Calculate. First, add the positive summands, next, negative ones and calculate the sum of the obtained results.

a) (- 5) + 12 + (- 8) + 9

b) 30 + (- 7) + (- 6) + (- 4)

c) (- 30) +17 + 6 + (- 4)

An extra task:

The sum of the subsequent integers equals – 4. How many numbers are there?

Lesson summarym0a42d0528af2970f_1528450119332_0Lesson summary

The students do the summarising tasks.

Then they sum up the class drawing the conclusions to memorise:

- The sum of two negative integers is the negative number.
- The sum of two positive integers is the positive number.
- The sum of the opposite number equals zero.
- To sum some integers you should add some positive summands first, then negative ones and calculate the sum of the obtained results.m0a42d0528af2970f_1527752263647_0- The sum of two negative integers is the negative number.
- The sum of two positive integers is the positive number.
- The sum of the opposite number equals zero.
- To sum some integers you should add some positive summands first, then negative ones and calculate the sum of the obtained results.

Selected words and expressions used in the lesson plan

negative numbernegative numbernegative number

positive numberpositive numberpositive number

integerintegerinteger

addition of the integersaddition of the integersaddition of the integers

opposite numbersopposite numbersopposite numbers

number less than zeronumber less than zeronumber less than zero