Something I just noticed as a pattern: the development of franchises that are constructed to "pace" the growth of the target audience.

E.g. in the Star Wars prequels the first movie had a lot of elements which aimed at a kiddy audience. This is quite distinct from having a child as one of the protagonists, extending also to theme and treatment. E.g., the child is ridiculously precocious, there are lots of cutesy characters, and the overall story is mostly a light adventure. (Poor plot & exposition, to be sure, but largely a quest with no internal conflict.) In the second & third movies, you've basically got sex & adolescence as major elements, and the tone becomes darker and more "mature". (Note I'm not saying those movies were terribly sophisticated or well-done, just that they took on the hallmarks of being targeted at older audiences than the first one.)

Now I think you've got a similar arc with Harry Potter--not only the characters mature but the tone and the seeming target audience as well. With the series Ben 10 (I have a nephew who's into it, I don't really know it myself) I find that "the storyline [of the sequel] is notable for having matured the character and taking a darker tone, with more complex plots, and sometimes more characters dying."

Think about this for a minute: there's no particular reason that a given story has to "grow up" in the sense of becoming dark/gritty/angsty just because the characters hit puberty. Or conversely there's no reason a story featuring child protagonists has to be softened for a putative child audience (e.g., Empire of the Sun).

As I consider this pattern, I'm not entirely sure I like it. On the one hand I feel that this sort of "tailoring" over time is harmful to the integrity of the story as a whole, and is becoming cliche as it gets repeated from one "franchise" to the next. On the other hand, these approaches seem to be a strategy of "hooking" and then retaining the commercial allegiance of entire cohorts--that is, it's not only artistically questionable but seems to be taking exploitation to a new level.

What do you think? And is this a new thing, or has it happened (to the same degree?) before? Off the top of my head, the Chronicles of Prydain seems to have followed a similar arc; possibly Earthsea does as well?

I'm not sure what offends you in this regards.  Aiming to keep the aging fan base happy by showing the familiar characters going through a similar aging process isn't particularly evil, if anything its less 'evil' than a process of 'fan churning', a la Warhammer.

In the cases of Harry Potter, its only appropriate that the characters age, its a valid authorial choice and one that is quite evident in the structure of even the first book of the series.

As for the Chronicals of Pyrdrain, while it has been well over a decade (more like two) since I actually read those, it still strikes me as entirely out of place in this discussion. More than anything else the Chronicles were about growing up and maturing into one's role, as far as I recall. They fit very nicely into the Hero's Journey, for good or ill, and NOT growing up would have aborted the chronicles right quick.

Right, then forget about Prydain; it's been even longer since I read that one, and from the little I can remember, the tone didn't change nearly as much as the others (I thought it was pretty juvenile throughout).

But about the others, to reiterate: of course characters age over time. What's odd though is that the story "matures" as well--to exaggerate a bit, going from cartoony to "adult".

It might help clarify what I'm talking about if we compared The Hobbit and The Lord of the Rings. The Hobbit is definitely a more "kid-friendly" book, even though I don't think it stoops to its audience or fails to be enjoyable for me as an adult. It has a more light-hearted tone, the characters are broader and funnier, overall it's more fairy-tale-like. Nobody important dies until the end, so there's no major theme of loss and grieving. But the characters in LotR and The Hobbit are about the same age. If Tolkien consciously chose to make LotR more "mature" for the sake of an audience that had been weaned on The Hobbit (which I don't know that he did), he didn't do so under cover of "portraying the process of growing up".

I believe that... and this is from a really shoddy memory... Tolkien wrote the hobbit at least partially as a bed time story to his son. I have also heard that he wrote the Lord of the Rings at least partially in the form of letters to his older son during the war.

Of course, like most stories, I don't fact check them at all and occasionally make shit up. Its not intentional, I have a feverish imagination and a tendency to dream my own life in a more surreal fashion.

I don't think you have it quite right, but I'm sure a couple minute's searching would turn up the real story.

http://en.wikipedia.org/wiki/The_Hobbit#Concept_and_creation (and see down the page for LotR).

I have a collection of his letters; he did write to his son with updates on his progress and ideas for LotR. And some of his other books were repackaged stories he'd written for his children, most notably The Father Christmas Letters.

I'd also throw in Narnia, written with particular children in mind, and with a strong element of maturation over the course of the series.