Flexible multiplicative strategies - multi digit numbers
This resource has been developed in partnership with the NSW Mathematics Strategy Professional Learning team, Curriculum Early Years and Primary Learners, and Literacy and Numeracy.
Using the resource
This resource is the third section of a four part resource supporting flexible multiplicative thinking. Use this resource in conjunction with the other resources in this series in order to support a connected network of critical mathematical concepts, skills and understanding.
Supporting tasks
Full instructions on how to use each of these tasks, including materials, related tasks and learning intentions are included in the resource, available for download on this page.
Task 1: Doubling and halving 2-digit numbers
Students double and half 2-digit numbers through visualising and using manipulatives.
Task 2: Repeated doubling
Students explore ways of thinking and develop fluency when doubling.
Task 3: Making landmark numbers: renaming for multiplication
Students understand the connection between strategies.
Task 4: Understanding the area method
Students use the area method of multiplication.
Task 5: If I know…
Students build number sense using the relationships between numbers and operations.
Task 6: Finding factors
Students use known facts to make problems easier to solve.
Task 7: Investigating more factors
Students manipulate numbers to make problems easier to solve.
Task 8: Using related facts
Students use related facts to flexibly solve division and multiplication problems.
Task 9: Leftovers
From Marilyn Burns, About Teaching Mathematics, 2015
Play the Leftovers video then have students explore remainders and fair share situations.
Task 10: How many ways can they be related?
Students develop efficient mental computation and strong number sense.
Task 11: Patterns of divisibility
Students investigate, notice and test generalisations and how useful they are in solving division problems.
Task 12: Dividing by partitioning the dividend (using the distributive property)
Students explore the concept of the distributive property.
Task 13: Factorising
Students use factorising to solve problems.
Task 14: Flip 3
Students think flexibly and strategically about the order solving multiplicative involving multiple factors.
Task 15: Dividing by factorising
Students explore the concept of dividing by factorising.
Task 16: Estimate me
Students explore ways they use estimation to determine the reasonableness of multiplicative solutions.
Task 17: What’s in a remainder?
Students understand remainders and fair share situations.
Task 18: Divide me this
Students understand factor-factor-product relationships and operating with division.
Task 19: Which would you work out in your head?
Students critique different strategies and problem situations.
Task 20: Target number
Students develop fluency with multiplicative situations.
Task 21: Investigating written methods for multiplication
Students explore and make sense of written multiplication methods.
Task 22: Investigating written methods of division
Students explore and make sense of written division methods.
Task 23: Doubling and halving-a number talk
Play the Doubling and halving – a number talk video then have students explore the relationship between doubling and halving.
Task 24: Let’s investigate 2 - 15 x 9
Play the Let’s investigate 2 – 15 x 9 video then have students think about efficiency in representing multiplicative situations.
Task 25: Fewest squares
Play the Fewest squares - part 1 video, Fewest squares – part 2 video and Fewest squares - part 3 video then have students to explore and make sense of square numbers.
Task 26: Jump! What if?
Play the Jump! What if? – part 1 video and Jump! What if? – part 2 video then have students think multiplicatively about ‘times as many’ scenarios.
Task 27: Super shapes
From NRICH maths
Play the Super shapes video then have students solve multiplicative problems where the product is known.
Task 28: Colour in fractions
Play the Colour in fractions video then have students explore equivalence in the context of fractions.
Task 29: Imagining fractions
Play the Imagining fractions video then have students explores visualisation and flexible strategies when combining fractions.