What you learn

Flash Vocal — Subtraction trains the subtraction tables from −1 to −10: for each table, the eleven subtractions whose answer goes from 0 to 10 (for the −4 table: from 4 − 4 to 14 − 4). An equation appears — “9 − 4 = ?” — and the child says the answer out loud. The app listens, validates and moves to the next one.

The answer is always positive: the app never asks a subtraction whose result would be negative, a notion children only meet much later.

The goal is not to know how to compute, but to answer without computing: nine minus four, five — like a nursery rhyme. This automatism is what frees attention for bigger calculations, at school as at home.

• Ages 6 — tables −1, −2, −3.
• Ages 7 — up to the −5 table.
• Ages 8 — all tables, −1 to −10.
• Remediation — older children, to fill missing automatisms.

The app is available in sixteen languages: English, French, German, Spanish, Italian, Portuguese, Dutch, Polish, Czech, Turkish, Catalan, Ukrainian, Russian, Japanese, Vietnamese and Chinese. It follows the device language and expects the answer in that language.