AC9M4A01 Year 4 Mathematics

This Content Descriptor from Year 4 Mathematics provides the specific knowledge and skills students should learn. Use it to plan lessons, create learning sequences, and design assessments that align with the Australian Curriculum v9.

find unknown values in numerical equations involving addition and subtraction, using the properties of numbers and operations

Elaborations

• 1 demonstrating the commutative properties of addition using materials, diagrams and number lines; for example, using number lines to demonstrate that \(5 + 2 = 2 + 5\), demonstrating that \(2 + 2 + 3 = 7\) and \(2 + 3 + 2 = 7\) and \(3 + 2 + 2 = 7\)
• 2 using balance scales and informal uniform units to create addition or subtraction number sentences showing equivalence, such as \(7 + 8 = 6 + 9\), and to find unknowns in equivalent number sentences, such as \(6 + 8 = \square + 10\)
• 3 using relational thinking and knowledge of equivalent number sentences to explain whether equations involving addition or subtraction are true; for example, explaining that \(27 \space– \space 14 = 17\space – \space4\) is true and using a number line to show the common difference is \(13\)
• 4 using part-part-whole diagrams or bar models to recognise and explain the inverse relationship between addition and subtraction, using this to make calculations easier; for example, solving \(27 + \square = 63\) using subtraction, \(\square = 63\space – \space27\)

Related Achievement Standards