Why number bonds matter
Knowing that 8 and 2 make 10 is the key to adding 8 + 5 in your head: 8 + 2 + 3. Bonds and fact families make that connection visible.In the Australian Curriculum
- FoundationPartitioning and combining collections up to 10 using part-part-whole relationships and subitising (AC9MFN04).
- Year 1Adding and subtracting within 20 using part-part-whole knowledge to 10 (AC9M1N04).
- Year 2Recalling addition facts to 20 and using them to work out related subtraction facts (AC9M2A02).
“Part-part-whole” is the curriculum’s own phrase from Foundation onwards, so the bond diagrams here match the words children hear in class. Bonds to 5 and 10 suit Foundation, and bonds to 20 suit Year 1.
Fact families fit Year 2, when addition facts are used to work out the related subtraction facts. That is exactly what the four facts in each triangle show: if 7 and 3 make 10, then 10 take away 3 is 7.
Summarised in our own words from the Australian Curriculum: Mathematics, Version 9.0 (ACARA).
