Learning objects The difference bar: make your own easy subtractions


Learn how to split up numbers in your head. Use a linear partitioning tool to help find the difference between pairs of numbers such as 8 and 64. Choose your own pairs of numbers (a single-digit number and a two-digit number). Split the numbers into parts that are easy to work with, work out each part and then solve the original calculation. This learning object is one in a series of five objects.

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.
  • Allows students to input a one digit whole number and a two digit whole number and find the difference between the entered numbers.
  • 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


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

    Other details

    • Technical implementer
    • Subject matter expert
    • Publisher
    • Date of contribution: 20 Sep 2013
    • Organisation: Education Services Australia
    • Address: Melbourne VIC 3000 Australia
    • URL: http://www.esa.edu.au/
    Access profile
    • Colour independence
    • Device independence
    • Hearing independence
    Learning resource type
    • Interactive Resource
    • Microsoft Internet Explorer - minimum version: 8.0 (MS-Windows) - maximum version: 9.0 (MS-Windows)
    • Firefox - minimum version: (MS-Windows)
    • Safari - minimum version: 5.1 (MacOS)
    Operating systems
    • MacOS - minimum version: 10.6
    • MS-Windows - minimum version: XP - maximum version: 7
    • © Education Services Australia Ltd, 2013, except where indicated under Acknowledgements.