About Number Bonds

Free number bonds practice for kids — master addition pairs and part-whole relationships with interactive exercises. Builds math fluency for ages 4-8. No ads, no sign-up.

How to use

1. Pick a level: Easy (bonds to 10), Medium (to 20), Hard (to 50), or Expert (to 100). Bonds to 10 align with Common Core 1.OA.6 and Singapore Math's Grade 1 'making 10' strategy — the foundation of mental addition.
2. Look at the yellow target circle at the top. Two smaller circles below must add up to it — one is given (purple), the other shows '?' (pink). Find the missing addend.
3. Tap the correct number from the choice grid below. The bond glows green when right; wrong picks shake and reveal the answer so kids learn the fact, not just the failure.
4. Use the visual bond diagram (lines connecting target to parts) to internalize part-part-whole reasoning. This same diagram appears in Eureka Math and most state-adopted K-2 curricula.
5. Aim for 10 questions per round. Watch the streak counter — research from Carpenter's 'Children's Mathematics' shows kids who automatize bonds to 10 progress 6-12 months faster on multi-digit addition and subtraction.
6. After 10 questions, you'll earn 1-3 stars. Tap Change Level to climb to bonds to 20 (matches Common Core 2.OA.B.2) or down to reinforce basics — there's no penalty for revisiting easier levels.
7. Parent tip: aim for 5-minute sessions, 4-5 days a week. The book 'Number Sense Routines' by Jessica Shumway recommends little-and-often as the highest-leverage K-Grade 2 math habit.

Frequently asked questions

Part of ToolFluency’s library of free online tools for Kids. No account needed, no data leaves your device.