In a Santa Claus children's story, the most interesting part might be how Santa knows which children are naughty or nice. It's a mystery. Is it some kind of magic? Or does he have little elves spying on kids all year? Also, the idea that he can carry so many presents for all the children in the world in his sleigh is quite fascinating. His sleigh must be really special with all that magic and the reindeer that can fly so fast. And the way he leaves the presents and the joy it brings to children the next morning is truly heart - warming.
For me, the most interesting part is when Santa travels around the world in one night. It's just so magical that he can visit so many places in such a short time with his reindeer - drawn sleigh.
I think the moment when Santa goes down the chimney is really cool. He's this big, jolly man in a red suit, and he squeezes down the chimney without any problem. And then he quietly arranges the presents under the tree. It's a part full of mystery and fun in a Santa Claus children's story.