My advice is this. For Christ's sake, don't write a book that is suitable for a kid of 12 years old, because the kids who read who are 12 years old are reading books for adults. I read all of the James Bond books when I was about 11, which was approximately the right time to read James Bond books.
Terry PratchettWhut's the plan, Rob?" said one of them. "Okay, lads, this is what we'll do. As soon as we see somethin', we'll attack it. Right?" This caused a cheer. "Ach, 'tis a good plan," said Daft Wullie.
Terry PratchettThe characters are the plot. What they do and say and the things that happen to them are, in a sense, what the plot is. You can't take character and plot apart from each other, really.
Terry Pratchett