# The part-adder: generate hard sums

TLF ID L94

Solve addition sums such as 58+27. Use a linear partitioning tool to help solve randomly generated addition sums. Learn strategies to do complex sums in your head. Split a sum 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 partition numbers to add numbers mentally.
• Students use a linear model to add numbers mentally.
• Students investigate strategies for adding numbers mentally.
Educational value
• Helps students develop mental strategies to simplify and solve addition problems.
• Includes a partitioning tool where students rename numbers in terms of parts.
• Provides hints giving explanations of three mental strategies: ‘doubling’, ‘making to the next ten’, ‘using tens and ones’.
• Encourages repeated use by incorporating randomly-generated problems.
• Provides an option to print a worksheet for each completed equation, containing the working out.
Year level

4

Learning area
• mathematics
Strand
• Mathematics/Number and algebra
Concept
• Mathematics/Addition
• Mathematics/Counting strategies
• Mathematics/Number patterns
• Mathematics/Number relationships
• Mathematics/Whole numbers
• Mathematics/Mental arithmetic
• 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
• 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
Browsers
• 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
Rights
• © Education Services Australia Ltd, 2013, except where indicated under Acknowledgements.