Melvil Dewey invented the Dewey Decimal System many years ago, and it is still in use in libraries today. The system categorizes nonfiction books by subject. All nonfiction books are given a number, and the library is organized in such a way that all books in the same subject can be found in the same general area. While the system can often feel overwhelming and mysterious to children, learning how it works is an important skill.

Introduce children to the library by taking a tour. Be sure the children know the difference between nonfiction and fiction books and explain that only nonfiction books are arranged by the Dewey Decimal System.

Show the children the call numbers on the sides of a few of the books. Be sure to point out that each book has its own special call number, like a fingerprint.

## Sciencing Video Vault

Make a "cheat sheet" that children can use to remember which call numbers are used for which book subjects. The first digits in the call numbers will direct children toward the book subject. For example, books about science have call numbers between 500 and 599, and books about technology have call numbers between 600 and 699.

Create a game to help children locate books in the library using the Dewey Decimal System. Assign random Dewey numbers to each child. Have the child locate the book using the number and a map of the library if necessary. Have the child bring the book back to the group and tell them the subject. Have children hypothesize what other kinds of books would be available in that same section.

Be sure to show children how to replace the book on the library shelf using the Dewey decimal numbers. Explain that the numbers help librarians place books on the shelves.