recognise and explain the connection between addition and subtraction as inverse operations, apply to partition numbers and find unknown values in number sentences

How Bloomi helps with this

This is a NAPLAN-year topic. Bloomi teaches it with a short explainer, guided practice, and NAPLAN-style questions — every one traceable to this exact code.

What this looks like in the classroom

• partitioning numbers using materials, part-part-whole diagrams or bar models, and recording addition and subtraction facts for each representation, explaining how each fact is connected to the materials, diagrams or models; for example, \(16 + 8 = 24\), \(24\space – \space8 = 16\), \(8 = 24 \space–\space 16\)
• using the inverse relationship between addition and subtraction to find unknown values with a calculator; for example, representing the problem, “Peter had some money and then spent \(\$375\), now he has \(\$158\) left. How much did Peter have to start with?” as \(\square – \$375 = \$158\) and solving the problem using \(\$375 + \$158 = \$533\); solving \(27 + \square = 63\) using subtraction, \(\square = 63\space – \space27\) or by counting on; \(27, 37, 47, 57, 60, 63,\) so add \(3\) tens and \(6\) ones, so \(\square = 36\)
• exploring First Nations Australians’ stories and dances that show the connection between addition and subtraction, representing this as a number sentence and discussing how this conveys important information about balance in processes on Country/Place