I created Dewey Decimal labels to help my students learn to locate books in the non fiction section of the library. I have included a set in blue polka dots, blue chevron, and blue strips. I have these same sets in red, purple, gray, orange, yellow, and green.
To use in your classroom or school library: print the files you need.
I laminated mine for durability. Then I hot glued the two sides to a wooden stick. (I painted old rulers or use paint sticks from your local paint supply store..) You can also use plastic shelf markers, but they can get expensive.
Place your new markers in your bookshelves wherever you need books labeled. This helped my students learn the Dewey Decimal system and find non-fiction books.