Year 2 number bonds: to 20 and bridging through 10
By Year 2, bonds to 10 should be automatic. The next step is bonds to 20 and using a ten as a stepping stone when a sum crosses a decade, for example 8 + 7 = 8 + 2 + 5 = 15.
Bonds to 20
| First | Second |
|---|---|
| 11 | 9 |
| 12 | 8 |
| 13 | 7 |
| 14 | 6 |
| 15 | 5 |
| 16 | 4 |
Relate each pair back to bonds to 10: 13 + 7 works because 3 + 7 = 10, so the remaining ten from 13 makes 20.
Bridging through 10
- Look at 9 + 6. Ask how many more to reach the next ten: 1.
- Split 6 into 1 + 5.
- Add: 9 + 1 = 10, then 10 + 5 = 15.
The same idea works backwards for subtraction: 15 − 6 is 15 − 5 − 1, landing on 9.
Classroom / home routine
- Two minutes of flash bonds to 10 every day.
- Then three bridging problems spoken aloud.
- Finish with one written number sentence the child explains in words.
Break down 17 in the tool, then ask what to add to make 20. Open the tool with 17
Year 2 bond practice
Fill each gap. Use bridging when it helps.
- 14 + ___ = 20
- 8 + 7 = ___
- 20 − 6 = ___
- 16 − 9 = ___
- 12 + 9 = ___
Show answers
- 6
- 15
- 14
- 7
- 21
Keep learning
Odd and even practice online: pairing, last digit and quick checksInteractive-style odd and even practice you can do with the Number Blocks Tool: pairing tests, last-digit rules, and mixed sums with answers.Prime numbers for kids: rectangles, tests and a first hundred chartA kid-friendly path into primes: build rectangles with blocks, learn why 1 is not prime, spot common traps, and practice with the Number Blocks Tool.Skip counting practice: 2s, 5s, 10s and linking to multiplesSkip-counting drills tied to place value and the Number Blocks Generator, with forward and backward patterns and answers.