8 - 9 years? There's a lot of violence in that... Like in most children's stories. And advanced vocabulary (a terrible thrashing, to peck, apologize, lavishly,...). But I'm sure they will get the point. And they will learn to deal with texts they don't understand completely. Like myself, for the first 20 years of learning English. You can ask if Momotoro would have made it alone, on his own. (They have to find out that the heroes succeeded only by combining their individual 'superpowers'.) And what they think about the dumplings. What would they use them for, if they had any? Do they know any secret ingredients? Family recipes?

I've a good idea! Hanging on to the pheasant the monkey scaled the gate and got inside. Once inside he unhinged the ###(lock/mock/mark/knob) on the door which promplty opened. We're in! said Momotoro and with a courageous cry they rushed in through the gate. Momotoro, you ###(punctious???) rascal, I'll thrash the ###(wits/white???) of(/off) you. The demon general went on the attack brandishing a large metal pole. Momotoro swallowed down a dumpling. Just one of the best dumplings in Japan and I gain the strength of a hundred warriors. Momotoro got hold of the demon general and threw him to the ground with a resounding crash - bang! What? Oh, that hurt! cried the demon. The dog barked (xx) and bit into the demon's leg. For the monkey screeched (xx), scratching the demon's face with his sharp fingernails. The pheasant then (xx), pecked at the demon's eye. Hey, that's enough of that. I've had it! Save me! The demon ran about frantically, tried to escape and received a terrible thrashing. With Momotoro's sword at his throat the demon general apologized: Please, forgive me, I promise I won't misbehave in the future. The demon's attendants all bowed their heads in remorse. I'll forgive you, so long as you don't misbehave in the future. Momotoro sheathed his sword and said: I'm going to return all the treasure(s) that you and your companions have stolen. I won't stand in your way. said the demon. Momotoro loaded all the treasure they had obtained from the demon onto a cart and they made their way home. They returned all the items to their rightful owners in the capital and in the villages. That was a fine achievement said the lord of the capital who rewarded Momotoro lavishly. But Momotoro shared his reward among the poor. The lord was more impressed than ever. Momotoro, I'd like you to marry my daughter. he said. Toasted by everyone Momotoro married the princess and lived happily ever after.