It's all still about having a good story. You have to have a good story as your anchor, as your main focus. So for me, personally, I just like to concentrate on writing the best book I can, and if there's other stuff that goes along with it, that's awesome, as long as the story is central.
I try to craft books that are fun, that are sort of subversively educational so kids learn but they don't really feel like they're being lectured to, and I want kids to always finish one of my books and think, "That was great, where's the next one?"
The most important thing whenever we're connecting kids to books, is that we try to match the book to the kid and make sure that reading is a fun, rewarding experience outside the classroom.
I think every writer struggles in some way with writers block. The trick is to plan out what you are going to say beforehand. I found out that if you make an outline you're much less likely to get blocked when you get into the middle of the story.
Kids, if anything, are harder to write for because they are a more discerning audience. They will not stay with you if you go off on a tangent or if you give them extraneous information that doesn't serve the story. You really have to tell a tight story. You have to give them humor and suspense and believable characters. All those things that adults want too, but you have to be really on your game when you're writing for kids.