Mathematics / Year 8 / Number

Curriculum content descriptions

use the 4 operations with integers and with rational numbers, choosing and using efficient strategies and digital tools where appropriate (AC9M8N04)

Elaborations
  • using patterns to assist in establishing the rules for the multiplication and division of integers
  • applying and explaining efficient strategies such as using the commutative or associative property for regrouping, partitioning, place value, patterning, multiplication or division facts to solve problems involving positive and negative integers, fractions and decimals
  • recognising the effect of sign in the multiplication of integers; for example, (-\(1)^4\;=\;1\) and (-\(1)^5\;=\) -\(1\)
General capabilities
  • Numeracy Numeracy
ScOT terms

Calculators,  Integers,  Number operations,  Rational numbers

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Output of a Solar Cell

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Moving out of home

This lesson explores costs and responsibilities associated with moving out of home and setting up living arrangements. The resource is part of a suite of lesson plans and activities from MoneySmart, designed to bring everyday financial topics into the classroom.

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MathXplosion, Ep 40: Kaprekar's operation

Did you know that 6,174 is a very mysterious number? In 1949, the mathematician Dr Kaprekar from India devised a process now known as Kaprekar's operation. First, choose a four-digit number where the digits are all different. Then rearrange the digits to get the largest and smallest numbers these digits can make. Finally, ...

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MathXplosion, Ep 1: Magic 9s

Follow these simple calculations to illustrate the special properties of the number 9. Pick your favourite number between 1 and 9 and multiply that number by 3. Add 3 to your answer. Multiply the result by 3. Treat your two-digit answer as two separate numbers and add them together. No matter what number you pick to start ...

Interactive

Arithmetic four

This is an interactive game for two students in which they solve arithmetic problems, similar to 'Connect four'. The players can choose to work with whole number and integer addition, subtraction, multiplication and division. The length of time each player will have and the level of difficulty of the problems can also be ...

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TIMES Module 10: Number and Algebra: division of whole numbers - teacher guide

This is a 26-page guide for teachers. This module contains a description of suitable models for division, a discussion of the types of problems that require division for their solution, and mental and written strategies for division.

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TIMES Module 14: Number and Algebra: fractions - teacher guide

This is a 16-page guide for teachers that provides an introduction to fractions. It covers ordering, the four basic arithmetic operations, cancelling, writing in simplest form, the use of the area model for multiplication and the use of the number line for ordering, adding and subtracting. A history of the development of ...

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TIMES Module 15: Number and Algebra: the integers - teacher guide

This is a 24-page guide for teachers. The module introduces the integers, order of the integers and operations on the integers.

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TIMES Module 9: Number and Algebra: multiplication of whole numbers - teacher guide

This is a 23-page guide for teachers. This module contains a description of suitable models for multiplication, a discussion of the types of problems that require multiplication for their solution, and mental and written strategies for multiplication. The use of the commutative, associative and distributive laws is described. ...

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MathXplosion, Ep 30: How many combinations can you get?

How many combinations can you get from 6 shirts and 4 pairs of pants? Determine the number of different outfits using the concept of possibilities (possible outcomes) and combinations.

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MathXplosion, Ep 17: Develop mathematical mind-reading skills

Amaze your friends with your super mind-reading skills. Here’s a brain game you can play by asking a few questions and substituting letters for numbers! Learn to follow a specific sequence of arithmetical steps to always arrive at the same answer.

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MathXplosion, Ep 11: Fun facts about the number seven

Did you know that the digits on opposite faces of dice will always add up to seven? Use dice as fun tools to reinforce fact families of seven, multiples of seven and subtraction skills.

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reSolve: Algebra: Tens and Units

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reSolve: Algebra: Addition Chain

This sequence of lessons explores making algebraic generalisations of sequences. Students use spreadsheets to investigate potential arithmetic relationships and then use algebra to identify and justify which relationships are generally true. The task can be used as a springboard for an in-depth exploration of the Fibonacci ...

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reSolve: Polygon Pieces

This lesson explores the geometry of cutting polygons in different ways and using algebra to express subsequent findings. Students use one straight cut to divide a convex polygon into two new polygons. They make generalisations about the total number of sides of the two new polygons, and about the number of different combinations ...

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reSolve: Algebra: Think of a number - Linear Equations

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reSolve: Quarter Cartons

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reSolve: Working with algebra

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Proportional reasoning video

Use this video as a springboard to explore scaling or proportional thinking, and to apply that thinking in a food context, drawing on reasoning and mathematical modelling.

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Catalyst: Take the Phi Golden challenge

The golden ratio, Phi: fact or fallacy? What about the Fibonacci sequence? We are told this ratio and its cousin Fibonacci occur everywhere in nature. Let's see which of these claims stacks up when put to the test.