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The difference bar: generate easy subtractions

TLF ID L111

Learn how to split up numbers in your head. Use a linear partitioning tool to help find the difference between pairs of two-digit numbers such as 25 and 34. In these examples, the difference is always less than ten. Split the numbers into parts that are easy to work with, work out each part and then solve the original calculation.



Educational details

Key learning objectives
  • Students use a linear model to solve differences mentally.
  • Students partition numbers and investigate strategies to solve differences mentally.
  • Students apply the associative principle to solve differences mentally.
Educational value
  • Encourages students to solve subtractions using mental strategies.
  • Provides a series of whole number pairs which students are challenged to find the difference between.
  • Provides hints for mental strategies that aid student subtraction skills.
  • Provides an option to print a worksheet for each completed equation showing the student’s working out.
Year level

3

Learning area
  • mathematics
Strand
  • Mathematics/Number and algebra
    Concept
    • Mathematics/Subtraction
    • Mathematics/Counting strategies
    • Mathematics/Whole numbers
    • Mathematics/Mental arithmetic
    • Mathematics/Number patterns
    • Mathematics/Number relationships
    • Mathematics/Algorithms
    Skill
    • Analysis;
    • Application;
    • Comprehension;
    • Knowledge
    Student activity
    • Interactives;
    • Analysis;
    • Experiment;
    • Modelling
    Learning design
    • Independent learning;
    • Experiential learning;
    • Problem solving;
    • Visual learning

    Other details

    Contributors
    • Subject matter expert
    • Technical implementer
    • Publisher
    • Date of contribution: 2016-09-28
    • Name: Education Services Australia
    • Organisation: Education Services Australia
    • Address: Melbourne VIC 3000 AUSTRALIA
    • URL: www.esa.edu.au
    • Copyright holder
    • Date of contribution: 2016-09-28
    • Name: Education Services Australia
    • Organisation: Education Services Australia
    • Address: AUSTRALIA
    • URL: www.esa.edu.au
    Metadata contributors
    • Resource metadata contributed by
    • Name: Education Services Australia
    • Organisation: Education Services Australia
    • Address: AUSTRALIA
    • URL: www.esa.edu.au
    Access profile
    • Colour independence
    • Device independence
    • Hearing independence
    Learning resource type
    • Tablet friendly (Interactive resource)
    Browsers
    • Google Chrome
    • Firefox - minimum version: (MS-Windows)
    • ms-internet explorer - minimum version: 9.0 (MS-Windows) - maximum version: 11.0 (MS-Windows)
    • Safari - minimum version: 7.0 (MacOS) - maximum version: 7.1 (MacOS)
    Operating systems
    • ms-windows - minimum version: 7 - maximum version: 10
    • macos - minimum version: v7.1 - maximum version: OS X 10.10 Yosemite
    Rights
    • © Education Services Australia Ltd, 2016, except where indicated under Acknowledgements. This material may be used in accordance with the Creative Commons Attribution-ShareAlike 3.0 Australia (CC BY-SA 3.0 AU) licence https://creativecommons.org/licenses/by-sa/3.0/au/.