Mathematics / Year 3 / Algebra

Curriculum content descriptions

extend and apply knowledge of addition and subtraction facts to 20 to develop efficient mental strategies for computation with larger numbers without a calculator (AC9M3A02)

Elaborations
  • partitioning using materials and part-part-whole diagrams to develop subtraction facts related to addition facts, such as \(8 + 7 = 15\) therefore, \(15 \space–\space 7 = 8\) and \(15\space – \space 8 = 7\)
  • using partitioning to develop and record facts systematically; for example, “How many ways can \(12\) monkeys be spread among \(2\) trees?”, \(12 = 12 + 0\), \(12 = 11 + 1\), \(12 = 10 + 2\), \(12 = 9 + 3\), …; explaining how they know they have found all possible partitions
  • understanding basic addition and related subtraction facts and using extensions to these facts; for example, \(6 + 6 = 12, 16 + 6 = 22, 6 + 7 = 13, 16 + 7 = 23\), and \(60 + 60 = 120, 600 + 600 = 1200\)
General capabilities
  • Critical and creative thinking Critical and Creative Thinking
  • Numeracy Numeracy
ScOT terms

Mental arithmetic,  Associativity,  Commutativity,  Subtraction,  Addition

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Addition Strategies - Calculate

Regular practise of addition facts can help children build their confidence in maths.

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Subtraction Year 3 & 4 - Calculate

This activity is designed to encourage students to develop and explain different strategies to solve subtraction problems.

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Park Ranger Problem Solving: An ‘Addition & Subtraction’ Rich Task for Years 3–4 - Calculate

The aim of this task is to provide a rich, contextual activity through which students can begin to explore the addition and subtraction of one- and two-digit of numbers in everyday contexts.

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Subtraction Strategies - Calculate

This game gives students opportunities to practice subtraction skills and to learn subtraction strategies, including the jump strategy, the split (or partition) strategy, compensation and the count-up to strategy (sometimes called the Shopkeeper’s method).

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Decimals Year 3 & 4 - Calculate

The focus of this activity is to find out what students know about addition of decimals and what are some of the different strategies students are able to use and explain. Do students prefer to use equations or do students rely more on empty number lines?

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Race to... - Calculate

This game challenges students to use their knowledge of place value to add and subtract random numbers in order to meet a target value.

Downloadable

First steps in mathematics: Number – Book 2

The content of this book is organised into topics including understanding operations, calculating, and reasoning about number patterns.

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ROWCO - Calculate

ROWCO is a card game that will help students practice their addition facts while playing an engaging strategy game.

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Pass The Count - Calculate

This game allows students to practice their skip counting skills in small groups.