Number bonds to 10
National Curriculum: expected secure by the end of Year 1.
What it is
Number bonds to 10 are the pairs of numbers that add to 10: 7 and 3, 6 and 4, and so on. Knowing a bond means more than being able to work it out — the aim is instant recall, so that "7 and what makes 10?" gets an answer without counting.
They matter because later arithmetic leans on them. Adding 8 + 5 by bridging through ten (8 + 2, then 3 more) only works if 8 + 2 = 10 is already automatic, and the same pairs come back in 70 + 30, in mental subtraction, and much later in decimals.
When children learn it
Children work on pairs within 5 in Reception and are expected to know the pairs to 10 by the end of Year 1 (ages 5 to 6). Year 2 then uses them constantly, because adding and subtracting across ten is built on them.
What it looks like when it goes wrong
These patterns come up again and again in children's answers on this skill. Each one points at a specific missing idea, not carelessness.
- A near miss instead of recall. Asked 7 add 3, they say 9 or 11. They are counting on rather than recalling, and the count slips by one. Counting on is the right method at an earlier stage, but a near miss here means the fact itself is not stored yet.
- Answering with the whole. Asked "6 and what makes 10?", they answer 10. They have heard the target number rather than the question — the idea that 10 is made of two parts, one shown and one missing, has not settled.
- Echoing the number they were given. Asked "6 and what makes 10?", they answer 6. The same gap from the other side: without a part-whole picture in their head, the question has nothing to attach to, so they repeat what they heard.
How to help at home
- Use fingers as a ten frame: hold up 7, ask how many are folded down. Ten fingers make the missing part visible instead of abstract.
- An egg box with ten spaces works the same way: put in 4, ask how many spaces are left. Seeing the missing part matters more than reciting pairs.
- Keep it short and frequent — two minutes at the table most days builds recall faster than an occasional long session.
- Say the whole fact family together: 7 + 3, 3 + 7, 10 − 3, 10 − 7. One pair carries four facts.