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Flash mental maths: add the numbers as they flash

For parents and teachers of children who learn mental arithmetic or soroban, from Year 1. Numbers flash one at a time; your child keeps the running total in their head and types the answer. Free, no sign-up.

This week's practice, to send to family →

How to use it with your child

  1. Choose the digits, how many numbers, and how long each one shows. Start slow: 1 digit, 5 numbers, 1 second.
  2. Tap Start on this device, then Ready? The numbers flash one by one, with a short beep (turn sound off if you like).
  3. Your child types the total. Afterwards the numbers that flashed are shown, so they can see where a slip happened.
  4. Speed up only when sets are right most of the time. Soroban learners can switch on with minus.
  5. Teachers: switch on projector for huge digits, and press Space or → to start each set.

Which school years it suits

One-digit flashes suit Years 1–2; two digits Years 3–6, especially for children who go to soroban (そろばん / 주산 / 珠算) classes.

Why flash practice works

Seeing each number for only a moment trains children to picture and hold numbers, which is what abacus learners do with an imagined soroban. The printed sheet gives the same numbers as columns (見取り算) for paper practice.

Ready-made links

Questions parents ask

Is this the same as soroban flash anzan?

It is the same format: numbers flash and the total is worked out mentally. Pencilhop doesn't teach the abacus itself; it gives practice at a steady pace.

Can I use it with a projector?

Yes. Switch on projector for very large digits; start each set with Space, → or Enter.