# YEAR 3 MATHS FOCUS

## NUMBERS AND ALGEBRA

Multiplication & Division

Learning Experiences

Multiplication & Division

## MULTIPLICATION & DIVISION

OUTCOME

A student:

MA2-6NA: uses mental and informal written strategies for multiplication and division

TEACHING POINTS | When beginning to build and read multiplication facts aloud, it is best to use a language pattern of words that relates back to concrete materials such as arrays. As students become more confident with recalling multiplication facts, they may use less language. For example, ‘five rows (or groups) of three’ becomes ‘five threes’ with the ‘rows of’ or ‘groups of’ implied. This then leads to ‘one three is three’, ‘two threes are six’, ‘three threes are nine’, and so on. |

In Stage 2, the emphasis in multiplication and division is on students developing mental strategies and using their own (informal) methods for recording their strategies. Comparing their own method of solution with the methods of other students will lead to the identification of efficient mental and written strategies. One problem may have several acceptable methods of solution. | |

Students could extend their recall of number facts beyond the multiplication facts to 10 × 10 by also memorising multiples of numbers such as 11, 12, 15, 20 and 25. | |

An inverse operation is an operation that reverses the effect of the original operation. Addition and subtraction are inverse operations; multiplication and division are inverse operations. | |

The use of digital technologies includes the use of calculators. |

Language | Students should be able to communicate using the following language: group, row, column, horizontal, vertical, array, multiply, multiplied by, multiplication, multiplication facts, double, shared between, divide, divided by, division, equals, strategy, digit, number chart. |

## Expectations of Attainment

Recall multiplication facts of two, three, five and ten and related division facts (ACMNA056) | count by twos, threes, fives or tens using skip counting |

use mental strategies to recall multiplication facts for multiples of two, three, five and ten | |

– relate ‘doubling’ to multiplication facts for multiples of two, eg ‘Double three is six’ (Reasoning) | |

recognise and use the symbols for multiplied by (×), divided by (÷) and equals (=) | |

link multiplication and division facts using groups or arrays, eg | |

– explain why a rectangular array can be read as a division in two ways by forming vertical or horizontal groups, eg 12 ÷ 3 = 4 or 12 ÷ 4 = 3 (Communicating, Reasoning) | |

model and apply the commutative property of multiplication, eg 5 × 8 = 8 × 5 |

Represent and solve problems involving multiplication using efficient mental and written strategies and appropriate digital technologies (ACMNA057) | use mental strategies to multiply a one-digit number by a multiple of 10, including: repeated addition, eg 3 × 20: 20 + 20 + 20 = 60 using place value concepts, eg 3 × 20: 3 × 2 tens = 6 tens = 60 factorising the multiple of 10, eg 3 × 20: 3 × 2 × 10 = 6 × 10 = 60 |

– apply the inverse relationship of multiplication and division to justify answers, eg 12 ÷ 3 is 4 because 4 × 3 = 12 (Reasoning) | |

select, use and record a variety of mental strategies, and appropriate digital technologies, to solve simple multiplication problems | |

– pose multiplication problems and apply appropriate strategies to solve them (Communicating, Problem Solving)Critical and creative thinking | |

– explain how an answer was obtained and compare their own method of solution with the methods of other students (Communicating, Reasoning) | |

– explain problem-solving strategies using language, actions, materials and drawings (Communicating, Problem Solving) | |

– describe methods used in solving multiplication problems (Communicating) |

Learning Experiences

To be added