Which would you do in your head? Image

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Which would you do in your head?

This resource invites students to think about how they currently operate with number before looking at how to solve 38 + __ = 66 using a bar diagram.

Additional details

Year level(s) Year 2, Year 3
Audience Student, Teacher
Purpose Teaching resource, Teaching strategies
Format Video
Teaching strategies and pedagogical approaches Questioning, Targeted teaching, Concrete Representational Abstract model
Keywords mental strategies,,,,,,,, written strategies, bar diagram, addition, subtraction, reasoning, fluency, understanding, explicit teaching

Curriculum alignment

Curriculum connections Numeracy
Strand and focus Number, Build understanding
Topics Place value, Addition and subtraction, Operating with number
AC: Mathematics (V9.0) content descriptions
Add and subtract one- and two-digit numbers, representing problems using number sentences and solve using part-part-whole reasoning and a variety of calculation strategies

Extend and apply knowledge of addition and subtraction facts to 20 to develop efficient mental strategies for computation with larger numbers without a calculator

Numeracy progression Additive strategies (P7, P8)
Number and place value (P5)
Number patterns and algebraic thinking (P3)

Copyright details


NSW Department of Education


© State of New South Wales (Department of Education), 2020 Creative Commons Attribution 4.0, unless otherwise indicated.