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 New Zealand Curriculum
- First 6 monthsAddition and subtraction facts to 5.
- Year 1Splitting 20 objects into smaller groups in different ways, such as 15 and 5, and basic addition facts to 10 with their related subtraction facts.
- Year 2Quick recall of addition facts, doubles and halves to 20, and missing-number sentences such as 18 + _ = 17 + 6.
Many New Zealand teachers describe this as part-whole thinking: once a child knows how a number splits, they can work with the parts instead of counting. Bonds to 5 suit the first months of school, bonds to 10 Year 1, and bonds to 20 Year 2.
Fact families match the way the curriculum pairs each addition basic fact with its subtraction facts from Year 1. Ask ākonga to write a missing-number sentence of their own from each triangle, which is Year 2 algebra.
Summarised in our own words from the New Zealand Curriculum: Mathematics and Statistics, Years 0–8 (in effect from 2025), and the Ministry of Education’s year-by-year guide for parents and whānau.
