Nancy Drew and the Mystery of the Library Alphabet

Nancy Drew, a young strawberry blond haired woman who lived with her father since her mother had passed away when she was a young girl, was visiting the local library one day with her boyfriend, football star Ned Nickerson, and was browsing in the Fiction section when she discovered something disturbing. The books seemed to have been alphabetized in a rather odd way. Rather than alphabetized in the section as you expect to find in a library or bookstore (where all the books by authors whose last names start with 'A' are at the beginning, authors with last names 'L' are in the bays and shelves in the middle, and authors with last names that start with 'Z' are at the end) the books were alphabetized shelf by shelf independent of other shelves, that is each shelf started with 'A' authors, proceeded through other letters of the alphabet, and ended with authors whose names fall at the end of the alphabet. The next shelf started over with 'A' authors and followed the same pattern.

"What kind of system for organizing and locating books is this?" she asked her boyfriend Ned.
"Maybe you should ask Bess, since she volunteers here at the library on the weekends," Ned replied, thoughtfully.

The following day, Nancy took Ned's sage advice and visited one of her two best friends Bess. When Nancy queried Bess about the odd organizational system in the Fiction section, Bess replied, "Oh, there is an explanation for that. You see, a teacher brought in some of her students to help out and apparently they are unfamiliar with how libraries are organized."

Bess continued her story, explaining to Nancy that a teacher at the school had heard of the passing of John Updike, and visited the library to find out what books by that recently departed author were available. Much to the dismay of the teacher, the Fiction section seemed to be shelved randomly with no concern for alphabet at all. Later that week, the same teacher had students arrive late to class. Now punishments in this school often include physical labor like weeding, but this teacher thought it would be good to have the students help organize in the library. She brought several students with her, and explained that the section was disorganized. That all the 'A' authors should be at the beginning, etc. leading to any 'Z' authors who would fall at the end. This teacher, thinking the explanation was clear, and that students had a working understanding of a library, sat down several rows away from the students and read her own book, checking occasionally on the students. It was not until it was almost time for them to leave that she realized they had been alphabetizing by shelf rather than by section. The students completed only one of three rows of shelves, so there is plenty of work still to be done. And thus this teacher is no closer to solving her own mystery of where the John Updike books might be located.