AC9M3A02 Year 3 Mathematics

This Content Descriptor from Year 3 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.

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

Elaborations

• 1 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 \(15\space – \space 8 = 7\)
• 2 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
• 3 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 \(60 + 60 = 120, 600 + 600 = 1200\)

Related Achievement Standards