Nothing fills me with dread quite like a middle-aged male writer announcing that he plans to write a YA novel just like the ones Robert Heinlein used to write . I could explain why this is such a harbinger of disappointment…but Charles Stross has already beat me to it. Instead, allow me to offer some non-Heinlein novels that succeed in scratching some of the same itches that the RAH juvies once scratched. For me, that requires the intended audience to include teens, that the genre be science fiction in the narrow sense, that the protagonist be a young adult, and that they get to do something that actually matters in the course of the book .
For the most part, I think RAH juv-a-likes work better when they are not series, but since I am not sure why that would be, I won’t insist on it.