F = Fiction 

Fiction book are marked with the letter 'F' and the first three letters of the author's last name

92 = Biography

Biographies are marked with the number 92 and the first three letters of the subject's last name.

E = Easy

Easy and early reader books are marked with the letter 'E' and the first three letters of the author's last name.

PS = Pre-K

 Pre-K books are marked with the letters 'PS' and the first three letters of the author's last name.

Numbers = Non-Fiction

Non-fiction books are organized by dewey decimal number. The Dewey Decimal system helps organize book by subject. You can also find handy subject signs on the shelves.