Yes, I you got whooshed. Besides the fact that the earlier epics are gone (leaving aside authorship questions) I mainly wanted to use “jump the scylla”.
As I child of twelve, I loved both of them.
I think the difference is, “Huckleberry Finn” is a serious novel disguised as a kids’ book, whereas “Tom Sawyer, Detective” Really is a kids’ book.
Either you paid very little attention to the OP or your grasp of arithmetic is akin to my grasp of string theory.
The “Who” doesn’t refer to de Camp – I figured people would know about him. It was referring to Johnny Black.
To my utter astonishment Voyager clearly knows who Johnny was. Or looked him up.
Did I miss something?
The OP asked Can anyone think of examples of series more than, say, eighty years old, that jumped the shark?
And Fiddle responded with a classic series, over 8 years old (more like 40) that definitely jumped the shark. Where is the math error?
Edited:
Ah, my can’t read eight/eighty goods at all. Maybe I needs more skool.
The Scarlet Pimpernel books by Baroness Orczy definitely did some shark-jumping. But it’s been so long since I’ve read any but the first, I can’t remember where the bad stuff starts.
“The Who” does refer to Tommy’s Holiday Camp, however.
You know, jsg, I almost posted that twice in this thread, but I couldn’t post that the original play and novel are classic with a straight face.
I’ve only read El Dorado besides Scarlet Pimpernel, too, so I couldn’t really say it ‘jumped the shark.’ Only that both were Edwardian pulp fiction.
Of course they’re classic! They’re OLD! 
Really, though, I adore the original book. I love it far too much for sanity.
I’ve seen all of the Savoyard operettas – even Thespis – and I can firmly say that the main reason that Utopia, Ltd. and The Grand Duke are rarely performed and relatively unknown is that they are very weak operettas. Gilbert and Sullivan just didn’t have the teamwork anymore after their split, and when they made these last two operettas, it showed.
If we’re going to be talking about the Trojan epics, the real shark-jumping was the Aenead. It’s basically just a retelling of the Odyssey, except this time, it’s my ancestor doing it, and he did it all better than your ancestor. If that counts as shark-jumping, and not just as fan-fic, at least.
I liked Tom Sawyer Abroad when I read it as a kid.
Oops. I misread that as “eight.” I was thinking, how young is this guy, if he thinks eight year old shows are “classic”.
Rosemary’s Baby was perfection. Son of Rosemary was painful.
I read Tom Sawyer, Abroad and Tom Sawyer, Detective back in grad school, and thought they were alright. I heard detective recently on audio, though, and thought it as painfu. Between it and Twain’s other eforts to write a detective story, I’ve decided that Twain couldn’t write a mystery to save his life – he’d rather write humor and social commentary.
I also read Tom Sawyer Amonng the Indians as a kid (It was published for the vfirst time in Life magazine, ages ago, and has been published in book form several times since), bu that shouldn’t count – he never finished it. Twain also started a story about Sawyer and Finn as old men, but he destroyed the manuscript. Looks like even their creator thought theyd Jumped the Shark.
I don’t think the* Betsy-Tacy *books were all that interesting after Betsy and the girls graduated from high school and Betsy married Joe.
The timeless classic “See Spot Run” was amazing. I was trembling inside as the book reached it’s dramatic climax. I’m sure I wasn’t alone with shedding a few tears as we all saw that Spot could, in fact, run. Wow! Does literature get any better?!
The follow up “Spot Can Run” was disappointing on almost every level. The series meandered along with “Spot Runs Fast”, but my interest was beginning to wane. The days of the author making bold choices, exploring uncharted literary waters, seemed to lose out to the desire to ‘play it safe’. Did Spot stop running? Was there a ball or a chew toy involved? These were questions that remained unanswered. We know the grass was green, but was it also soft? We’ll never know.
When the new characters of Bill and Sue were introduced, the love affair with the series was definately at an end; the proverbial ‘shark’ had been jumped. By the time the author came out with “Bill and Sue Run with Spot” I had already moved on to greener pastures and the edgy, intense literary firecracker of “Sam and Ann Play Ball”.
It’s not anywhere near a “classic”, but since we are talking about books, I think the most obvious series to jump the shark is the Xanth series. It was never great literature, but it was great stuff to read. All of the great characters dissappreared really quickly though.
So will you allow for a 72 year old series?
The Andy Hardy movie series had really jumped the shark despite it retaining its popularity after the last of the ones with Judy Garland. That was Life Begins for Andy Hardy in 1941. There were 4 that followed it and 12 years later Andy Hardy Comes Home (1958)
Not that I really care, but I was trying to think of a pre-TV classic series that had a chance to jump the shark. I watch way too much TCM.