3.OA.B.5
Apply properties of operations as strategies to multiply and divide.2 Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
26 Lessons
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Decomposing Arrays, Day 13rd Grade Math» Unit:Using Multiplication to Find Area
3rd Grade Math
» Unit:
Using Multiplication to Find Area
Big Idea:Students need to practice deconstructing arrays with manipulatives in order to conceptualize the distributive property. This 3 day lesson takes the children through increasingly sophisticated activities to explore the "why" and "how" of this property.
Multiplication Using The Commutative Property3rd Grade Math» Unit:Multiplication 2
3rd Grade Math
» Unit:
Multiplication 2
Big Idea:Understanding the commutative property of multiplication helps students master math facts.
Distributive Property, Day 13rd Grade Math» Unit:Using Multiplication to Find Area
3rd Grade Math
» Unit:
Using Multiplication to Find Area
Big Idea:Children need to move from the manipulative expressions of the distributive property into the mathematical equations eventually. This lesson is the first step in leading them to that goal.
Associative Property3rd Grade Math» Unit:Understanding Multiplication
3rd Grade Math
» Unit:
Understanding Multiplication
Big Idea:Children need to understand why the mathematical properties work and how they are applied. In this lesson, we explore modeling and "proving" the associative property.
Distributive Property, Day 23rd Grade Math» Unit:Using Multiplication to Find Area
3rd Grade Math
» Unit:
Using Multiplication to Find Area
Big Idea:The children have been practicing decomposing areas and now digits in order to understand and use the distributive property.
Decomposing Given Large Areas, Day 33rd Grade Math» Unit:Using Multiplication to Find Area
3rd Grade Math
» Unit:
Using Multiplication to Find Area
Big Idea:Students have been working with decomposing arrays in order to practice finding small areas and putting the totals together. In this third lesson, they will work on finding smaller areas that make the mental math more feasible.
Fun with Four: Decomposing to Known Factors of 1, 2, and 53rd Grade Math» Unit:Multiplication
3rd Grade Math
» Unit:
Multiplication
Big Idea:Students act as problem solvers to take an unknown fact and solve it by breaking it down into pieces that are known.
Associative Property With Manipulatives3rd Grade Math» Unit:Understanding Multiplication
3rd Grade Math
» Unit:
Understanding Multiplication
Big Idea:Children need to understand why the mathematical properties work and how they are applied. In this lesson, we explore modeling and "proving" the associative property.In this lesson, we explore modeling and "proving" the associative property.
The Multiplication and Division Connection3rd Grade Math» Unit:Sharing Equally with Division
3rd Grade Math
» Unit:
Sharing Equally with Division
Big Idea:Students can solve multiplication and division problems quickly by recognizing the relationship between the two operations.
Arrays, Arrays, Arrays3rd Grade Math» Unit:Multiplication
3rd Grade Math
» Unit:
Multiplication
Big Idea:Rearranging arrays to understand equivalent products.
Multiples in a Minute5th Grade Math» Unit:Multiplication Madness
5th Grade Math
» Unit:
Multiplication Madness
Big Idea:Understanding multiplication is repeated addition is the first step in understanding the concept.
Discovering Relationships: Multiplication & Division (1 of 2)3rd Grade Math» Unit:The Relationship Between Multiplication and Division
3rd Grade Math
» Unit:
The Relationship Between Multiplication and Division
Big Idea:Fact families include the same amount of total objects but the groups and number in each group can be manipulated.
Multiplication Properties4th Grade Math» Unit:Multiplication and Division Meanings
4th Grade Math
» Unit:
Multiplication and Division Meanings
Big Idea:Multiplication Properties are rules that can be used to help with math computation.
Using the Multiplication and Division Relationship to Solve3rd Grade Math» Unit:Sharing Equally with Division
3rd Grade Math
» Unit:
Sharing Equally with Division
Big Idea:Students can solve multiplication and division problems quickly by recognizing the relationship between the two operations.
Decomposing Given Large Areas Day 23rd Grade Math» Unit:Using Multiplication to Find Area
3rd Grade Math
» Unit:
Using Multiplication to Find Area
Big Idea:In this second of a three-part lesson, students extend decomposing arrays to applying a strategy for mental computation of area by finding smaller areas.
3.OA.B.5
Apply properties of operations as strategies to multiply and divide.2 Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
3.OA.B.6
Understand division as an unknown-factor problem. For example, find 32 ÷ 8 by finding the number that makes 32 when multiplied by 8.