3.20

The student will

a) investigate the identity and the commutative properties for addition and multiplication; and

b) identify examples of the identity and commutative properties for addition and multiplication.

Investigate the identity property for addition and determine that when the number zero is added to another number or another number is added to the number zero, that number remains unchanged. Examples of the identity property for addition are 0 + 2 = 2; 5 + 0 = 5.
Investigate the identity property for multiplication and determine that when the number one is multiplied by another number or another number is multiplied by the number one, that number remains unchanged. Examples of the identity property for multiplication are 1 x 3 = 3; 6 x 1 = 6.
Recognize that the commutative property for addition is an order property. Changing the order of the addends does not change the sum (5 + 4 = 9 and 4 + 5 = 9).
Recognize that the commutative property for multiplication is an order property. Changing the order of the factors does not change the product (2 X 3 = 3 X 2).
Write number sentences to represent equivalent mathematical relationships (e.g., 4 x 3 = 14 - 2).
Identify examples of the identity and commutative properties for addition and multiplication.

Textbook Correlation

Links to Related SOL

3.20 4.16b 5.19 6.19 7.16 8.15c

On-Line Games and Practice:

studyzone.org: Commutative Property Lesson
Mini-Lesson on commutative property and on-line practice

studyzone.org: Identity Property Lesson
Mini-Lesson on identity property and on-line practice

quia.com: Properties and Equality
Game about properties and equality

mathjourneys.com: Equality Math: Addition
Hands-on matching activity - students match two addition problems to show equality

mathjourneys.com: Equality of the Move: Addition
Students put themselves in pairs as they find the person with a matching sum

mathjourneys.com: Equality Match – Addition and Subtraction
Hands-on activity where students match an addition problem to a subtraction problem

mathjourneys.com: Equality Match – Mixed Operations
Hands-on activity where students match +, -, and x problems to show equality

mathjourneys.com: Equality Match – Mixed Operations II
Hands-on activity where students match +, -, and x problems to show equality

Teacher Reference:

uen.org: The Commutative Cookie
Lesson plan for illustrating the commutative property using unifix cubes

northstarmath.com: Commutative Property
Explanation of the property

northstarmath.com: Identity Property
Explanation of the property

multiplication.com: Commutative Property
Video explaining commutative property using cookies

misterteacher.com: Commutative Property
Explanation of commutative property

glencoe.com: Commutative Property
Video explaining the property

demonstations.wolfram.com: Commutative Property of Multiplication
Demonstrations with area models

learnnc.com: Introduction to Fact Families
Lesson plan where students create examples that demonstrate commutative property

studyzone.org: Commutative Property Lesson
Examples and a practice page

alex.state.al.us: Fish Eyes
Complete lesson plan with story and manipulatives

lessonplanspage.com: Commutative Property of Multiplication
Hand-on demonstration of the commutative property of multiplication

northstarmath.com: Properties
Addition and multiplication properties

northstarmath.com: Commutative Property
Explanations of property

northstarmath.com: Identity Property
Explanations of property

misterteacher.com: Commutative Property
Explanation of commutative property

solving-math-problems.com: Identity Property of + and X
Explanations and examples of the properties

elemendu.ccs.k12.nc.us: Properties
Several resources on various properties of + and X

learnnc.com: Introduction to Fact Families
Lesson plan where students invent examples that demonstrate commutative property

nsa.gov: Out of This World Multiplication
Complete 3 day lesson plan to create and extend patterns using multiplication

shodor.org: Patterns, Functions and Algebra
3 activities that go with 3.25a

illuminations.nctm.org: Multiplication: It’s in the Cards
Activities using a calculator and multiplication chart to learn about commutative property

Free Worksheets:

education.com: Identity Worksheet
Pre-made worksheet

tulyn.com: Identity Property Worksheet
Pre-made worksheet

mathcrush.com: Commutative Property
Addition worksheets that encourage using commutative property to group easy facts together