Here in Japan, the second grade school kids have to learn a multiplication method called 'Kakezan-Kuku'. This method is the reason why Japanese kids have a good track record of mathematics at the high-school, graduated the grade school.
It's important to repeat and repeat learning the kuku method, so this app is for you.

You can select a row(s) called 'Dan' in Kuku as you like.
Tap the play button at the top left, the player will be there. Robo will read you out to the Kuku to be familiar with it by ear.

Now, it's time to be a hero at school!