Obviously, a series can range anywhere between four and 100+ books. However, the most important consideration is how long should it ideally be and still be worthwhile. Even the best-written, most original series start to feel like mindless tosh and cash cows after a certain point.
I’m embarrassed when I think back on how many spin-off series I had planned or in progress for my Atlantic City characters, all branching off from the now-shelved eight-book first series I wrote. I even planned the titles and general plots of my entire Max’s House series when I was only writing the first book!
Looking through the list now (and at my synopses files), it’s obvious many can be combined, since they lead right into one another and are so short. Others can be tossed out entirely, since those events have been moved to separate books (e.g., Newark Love Story, Malchen and Pali).
A number of the titles originally referred to much different storylines, particularly re: Max and Sam’s intense, on-again, off-again relationship. Though Max is a major playboy in his younger years, the only serious relationships he ever has are with Al Scots (his future wife) and Brooke Pembroke (whom he breaks up with to reunite with Al). He goes on a couple of dates with Sam, but that’s pretty much it!
A lot of the insipid ones in the middle can be replaced with books with new titles and radically different storylines, spanning longer periods. It’s so obvious I was taking notes from after school specials, junky pulp fiction, and dreadful TV shows and movies about teens!
I’ve long known my Russian novels will span 1917–91 and include two prequels spanning 1889–1917. For Cinnimin, I know it’ll span 1941–2050 and end with Cinni’s death. Along the way, younger generations rise to the fore.
For Max’s House (a name I may very well change again), I originally planned it ending with Max and Al’s emotional reunion in autumn 1962, their marriage, and the birth of their first child. I knew all along Al is the only woman for him, no matter how much he takes her for granted, has an open relationship without her approval, breaks up with her to date other ladies, and finally has the tables turned when Al breaks their engagement and moves to Paris for five years. The entire series is driving towards this ultimate goal of happily ever after.
Now the series is slated to end in 1970, as the Sewards come together to bury patriarch Great-Grandpa Stanley and reflect on the end of an era. The world he opened his eyes to in 1860 was radically different than the one he closed his eyes on 110 years later.
For my permanently shelved WTCOAC series, I went the classic route of coming-of-age, taking my characters from fifth grade through the eve of starting college. I also planned a four-book series about their college years, plus a novel about their first year in the real world.
The prequel series is short and sweet, reflecting their young age (though there’s still some edgy content). As originally written, it takes them from the summer before second grade to their final day of fourth grade. If I age them up slightly, they’ll go from the summer before fourth or fifth grade to the last day of sixth or seventh grade.
So how many books are needed to tell a coming-of-age story or take a family and/or town through several generations?
I would say between seven on the lower end to maybe thirty on the highest end. Phyllis Reynolds Naylor’s Alice series runs 25 books, but it never feels like a wandering series. Alice ages normally, and as the series progresses, the books last longer (e.g., going from four books about one school year to only two, plus summer books). The first book and the three prequels last one school year, and the finale takes Alice from age 18–60.
At a certain point, a series starts to run out of steam and do little but serve a cash cow, esp. with floating timelines enabling characters to stay the same age for over 100 books. You need to have an idea of where you ultimately want to go, or you’ll just begin writing aimlessly, with no end in sight and characters long overstaying their welcome.
Most importantly, writing a neverending series prevents you from creating new characters and going on the journey through life with them. Goodbye isn’t forever when you can always reread the old books.