Scholastic Book Barcodes Are Not Scanning...Why?

Hello,

I am trying to scan my class collection of books and there are a lot of scholastic books that have barcodes but the app says "No books found for the given ISBN". Some of the scholastic books will scan but a large amount are not. Is there something else I need to do to scan it?

>1 Emery339: Is there maybe another barcode inside the front cover? Some of my middle-aged paperbacks have a barcode on the back cover that does not work and a second barcode inside the front cover that does work.

>1 Emery339: You may also want to check what sources you have selected in the App. Amazon or some library sources may not have the specific ISBN that you're scanning.

If scholastic doesn't sell those editions to libraries or through Amazon you won't find them through add book