How it works
A subtraction with the taken-away number hidden — 13 − ? = 7 — and five tiles to choose from. The difference is always 1 to 9 and nothing ever dips below zero. Solving it means reading a subtraction as the gap between two numbers, which is the understanding that makes the facts stick.
Practises
- Subtraction facts
- Fact families
Suited to
Classes 2–4
.