Find the Missing Number — Accessories — Grade 1

This is subtraction with the taken-away part left blank. A group of hats, belts and a scarf is shown with the number remaining; the child supplies how many were removed. It nudges a child past one-direction take-away toward seeing subtraction as a relationship — start, change, result — where any one can be the unknown. The accessories are concrete and the numbers within twenty, so the missing part is always reachable by counting, and a child can prove their answer rather than guess it.

Working a subtraction backward — from result to the part that left — is how a child first sees that the same three numbers can be arranged more than one way. It is the seed of fact families, a Grade 1 idea, and finding the missing part with within-twenty accessories keeps that seed planted in counting the child can actually do.

Children who like accessories take to the puzzle of working backward, and it suits a child ready for a little more than plain take-away. When this feels easy, try find the missing number with animals, or find the missing number with more birds. You can also browse every subtraction worksheet or the whole accessories collection for grade 1 — each sheet prints cleanly in black and white or plays online for free.