Mathematics / Year 3 / Number and Algebra / Number and place value

Curriculum content descriptions

Recall addition facts for single-digit numbers and related subtraction facts to develop increasingly efficient mental strategies for computation (ACMNA055)

Elaborations
  • recognising that certain single-digit number combinations always result in the same answer for addition and subtraction, and using this knowledge for addition and subtraction of larger numbers
  • combining knowledge of addition and subtraction facts and partitioning to aid computation (for example 57 + 19 = 57 + 20 – 1)
General capabilities
  • Numeracy Numeracy
ScOT terms

Mental arithmetic,  Subtraction,  Addition,  Associativity

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Addition and Subtraction - Calculate

This game focuses on addition, subtraction and estimation. It can be played many times as the totals will often be different and the focus of the mathematics can change. There is a video included to help with how to play the game.

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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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Salute - Calculate

This game gives students opportunities to practise addition and subtraction strategies and develop algebraic thinking by finding unknown values in additive equations.

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Musical fractions

Break down a song by counting how long the notes are in action! Learn about patterns in rhythms and musical notes, and discover the role of fractions in denoting whole, half and quarter notes and creating distinct sounds.

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Fun with fractals

Do you know how to recognise a fractal? Watch this video to find out! What are the examples given of fractals found in nature? Can you think of any others? Why not have a go at doing your own drawing of the Sierpinski Triangle?

Interactive

The difference bar: go figure

This tutorial is suitable for use with a screen reader. It explains how to split up numbers in your head when finding the difference between two numbers such as 26 and 73. Work through sample questions and instructions explaining how to use linear partitioning techniques. Find the difference between pairs of numbers. Split ...

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What is a fractal?

Do you know what a fractal is? Basically, fractals are never-ending patterns created by repeated mathematical equations. In this clip, Yuliya, a student at MIT (in the USA) describes the properties of fractals and shows you where they can be found in technology and nature. Have a good look at the world around you and see ...

Interactive

The number partner: go figure

This tutorial is suitable for use with a screen reader. It explains strategies for breaking up numbers into pairs of smaller numbers, eg 15 = 11 + 4. Work through examples of whole number pairs and sample questions. Apply these principles to solve additions or subtractions.

Interactive

Circus towers: square stacks

Work out how many acrobats are needed to form square-shaped human towers. Start by building a square tower with four acrobats: two acrobats in the base layer and two acrobats standing on their shoulders. Examine a table and graph of the total number of acrobats in the towers. Predict the number of acrobats needed to build ...

Interactive

Divide it up: grouping tool

Use a dividing tool to make equal shares of stationery such as pens, pencils or crayons. Complete a sentence describing a number operation. For example, pack 24 crayons into packets of 5. Predict how many packets are needed and identify how many items are left over.

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Mixed Up Maths, Ep 11: Funny money

What do you use money to buy? In this clip we look at Australian money. See the different coins and notes that make up our money system. We investigate if size, (in coins) does matter. Check out how many 5 cent pieces you need to make two dollars. We also look at some currencies used around the world. Find out which country ...

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BTN: What is an abacus?

An abacus is a tool that helps people solve maths problems. Why might some people still use, and encourage the use of, an abacus when there are more contemporary tools like calculators?

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What is a quarter?

What is a quarter? You get quarters when you divide a whole into four equal parts. Each one of these four parts is a quarter. Watch this great explainer produced by Monique in collaboration with ABC Splash and see how she explains quarters.

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Fractions in the real world

How many quarters make up a whole? Watch this video to find out how else you can represent 2/4 and how to add up quarters to make a whole.

Online

TIMES Module 3: Number and Algebra: multiplication and division - teacher guide

This is a 23-page guide for teachers. This module contains a description of suitable models for multiplication, a discussion of the type of problem phrased in words that requires multiplication for its solution, and mental and written strategies for multiplication. The use of the commutative, associative and distributive ...

Online

TIMES Module 2: Number and Algebra: addition and subtraction - teacher guide

This is a 29-page guide for teachers. The module introduces addition and subtraction of whole numbers.

Interactive

Sites2See: Patterns and Algebra

Selected links to a range of interactive online resources for the study of patterns and algebra in Foundation to Year 6 Mathematics.

Interactive

Summing Decimals

An interactive resource in which students learn how to add and subtract numbers that have up to two decimal places.

Interactive

The array

Use an array-building tool to help solve multiplications. Explore strategies to break up multiplications. Create and solve easy multiplications such as 9x3. Examine relationships between rows, columns and areas in arrays.

Interactive

Musical number patterns: musical times

Make some music by building up rhythms from four instruments. Make a counting rule that matches a pattern on a number line. Select the start number and then select a number to count by. For example, describe a sound pattern where a saxophone waits on the first note, and then plays on every eighth note. Add a second number ...