Founder story
I Had No Idea How Many Books Were In My Classroom Library. It Was 299 — And I'd Bought Duplicates.
I've been building my classroom library for over a decade, one book at a time — book fairs, garage sales, hand-me-downs from other teachers, the odd Scholastic order. I never once counted what I had. I couldn't have told you if you'd asked. It turns out the answer was 299 titles, and I'd bought duplicate copies of at least a few of them without ever realizing it.
How many books do you actually have in your classroom library?
If you're a teacher who's built your own classroom library over the years, I'd bet you can't answer that question either — not with a real number, just a general sense of "a lot" or "not enough." That was me. Books came in waves — a box from a retiring colleague, a stack from a book fair, whatever caught my eye at a used bookstore over the summer. Nobody was tracking any of it. Why would you? There was no reason to count books on a shelf, until I actually needed to know.
The school grant process made this worse, not better. Every so often I'd get a grant to buy new books, which meant digging through my own shelves first to figure out what I already had so I wasn't buying it again. Except a chunk of those books were never actually on the shelf — they were out with students. Trying to account for books that were currently checked out, from memory, while a grant deadline was approaching, is exactly the situation where you end up guessing instead of checking. More than once I guessed wrong.
Genre gaps you can't see until you count
The first thing that surprised me wasn't the total — it was how lopsided the collection turned out to be once I actually broke it down. I had shelves that looked full but were quietly one genre deep. Realistic fiction, sure, plenty of that. But when a student who only reads graphic novels or nonfiction came looking for their next book, I'd be guessing at what I actually had, because I'd never looked at my library that way before. You don't see a gap in a pile of books. You see it in a list.
The problem with buying more books from an author your students love
This is the moment that actually got me started. Gordon Korman was popular with my class that year, and I went to buy a few more of his titles to round out what I had. Except I had no idea which ones I already owned. I was standing there trying to remember covers from memory, which is exactly as unreliable as it sounds. I ended up guessing — and later found out I'd bought a book I already had two copies of, sitting on my own shelf the whole time.
That's the moment the problem stopped being "I should get organized someday" and became "I am actively wasting money because I don't have a list."
What I tried before I found a system that actually worked
I couldn't tell you exactly how long the whole process took, honestly, because so much of it was troubleshooting rather than scanning. I went through a couple of different scanners and databases before landing on one that worked. One database in particular wasn't good enough — a lot of books simply slipped through the process because their barcodes weren't recognized, which meant going back and figuring out, book by book, why the scan hadn't worked and how to fix it. There were other snags along the way too. None of it was scanning in the smooth, one-after-another way I'd pictured going in — it was a lot of stopping to fix the thing that wasn't working before I could keep going.
The setup that actually worked: an inexpensive scanner and my iPhone
What finally worked was much simpler than I expected. I picked up an inexpensive barcode scanner from Amazon, paired it with my iPhone, and started scanning the ISBN barcode on the back of every book. Scan, next book, scan, next book. No typing titles by hand, no guessing at authors' spelling. That's how I got to a real number — 299 — and how I found the duplicates and the genre gaps in the first place. Once I could see the whole collection as an actual list instead of a wall of spines, the gaps and the duplicates were obvious.
That scanning process is the part that eventually became Dewi. I built it because I wanted the rest of it — the catalogue, the circulation tracking, knowing which student has which book right now — to be as simple as that first scan.
The scanner I actually use: a PecuMecu wireless 2D barcode scanner — inexpensive, pairs easily, and reads ISBN barcodes cleanly. Disclosure: as an Amazon Associate, Dewi may earn from qualifying purchases through this link.
What that same scanner is doing for me now: tracking where books actually go
Once I had a real catalogue, the same inexpensive scanner turned out to be just as useful for the ongoing problem — not just counting what I own, but tracking where it goes once students start borrowing it. Now when a student checks out a book, I scan it out; when it comes back, I scan it in. I know exactly which student has which book at any given moment, instead of trying to remember or asking around the room. And if a book comes back damaged or defaced, I can note that at the moment it's checked back in, tied to that specific copy — rather than discovering the damage weeks later with no idea when or how it happened.
Frequently asked questions
How do I count how many books are in my classroom library?
The fastest accurate way is scanning each book's ISBN barcode rather than typing titles by hand — a barcode scanner paired with a phone or tablet turns a shelf of books into an actual searchable list in the time it takes to scan each spine once.
Do I need an expensive scanner to catalogue a classroom library?
No — an inexpensive barcode scanner from a general retailer, paired with a smartphone, is enough to catalogue a few hundred books. You don't need library-grade equipment built for a full school collection.
How do teachers avoid buying duplicate books for their classroom library?
The core issue is usually not having a searchable list of what you already own. Once your collection is catalogued — even a simple list with author and title — you can check it before buying instead of relying on memory.
How can I tell which genres my classroom library is missing?
You generally can't tell by looking at a shelf — a full-looking shelf can still be heavily skewed toward one or two genres. Cataloguing your books with genre tags is what actually surfaces the gaps.
How do I track which students have which classroom library books checked out?
Scanning a book's barcode at checkout and again at return, tied to that student, gives you an up-to-date record of exactly who has which book — including whether a specific copy came back damaged, without relying on memory.
What is Dewi?
Dewi is a classroom library and literacy platform built for teachers who manage their own classroom collection. It handles barcode-based cataloguing, circulation tracking (who has which book), and includes print-ready literacy activities. A School plan extends this to bulk licensing across a whole school.
Curious how many books are actually on your shelves? Start cataloguing free at getdewi.com.
Try Dewi free