Practise number bonds to 20 with part-whole diagrams — one value is left blank to fill in, and every sheet prints with a matching answer key. Bigger part-whole pairs that stretch number sense past ten. Free, no signup.
Generate a number-bonds-to-20 sheet →Opens the builder set to bonds that make 20 · 12 bonds · free, no signup.
Quick way to teach it: Lean on the bonds to 10 you already know: 14 and 6 make 20 because 4 and 6 make 10, plus a full ten. Two ten-frames show it clearly.
A number bond is a simple diagram showing how a "whole" splits into two "parts." For bonds to 20, the whole is 20 and the two parts add up to it — like 10 and 10. Bonds to 20 extend the make-ten idea across the teens. They build the fluency Grade 1–2 kids need before two-digit addition and subtraction.
Bonds to 20 are usually taught in Grade 1 & Grade 2. Each worksheet leaves one value blank — sometimes a part, sometimes the whole — so kids practise both adding the parts and finding a missing part.
Lean on the bonds to 10 you already know: 14 and 6 make 20 because 4 and 6 make 10, plus a full ten. Two ten-frames show it clearly. Print a fresh sheet, work a few each day, and check with the answer key — short, regular practice beats one long session.
Yes — completely free, no account, no email, no watermark. Every click generates fresh bonds with a matching answer key. Print as many as you like.