This is a game to improve your mental arithmetics and calculus (your children also can!) but having fun at the same time.
There are several game modes, just normal mathematics for you to practice and an Arcade Mode in which you will fight to survive doing math operations while being attacked by Math Ninja!! throwing you shurikens, bombs, etc.
Math calculus and mental arithmetics are really important in real life for everyone of us. Normally maths are forgotten as they seem to be arid for childrens and adults, but playing it like a game, trying to beat your own record and seeing how the difficulty slowly increments you will find that in a very few sessions your mental mathematics skills will improve a lot.
And that is a wonderful achievement for everyone of us as you will use them for everything, from just training your brain, just enjoyment, check how much you have to pay in the supermarket or how much should anyone pay in the restaurant.
Having a young brain is really important for us all and having fun at the same time it is just GREAT!