The Artemis Fowl Series, written by Eoin Colfer is one of the best books for children ever written in English. Those who enjoy reading fantasy and fiction would absolutely adore this book.
The main character, Artemis Fowl, is a twelve year old criminal mastermind that lives to solve cases that may in fact lead the world to an end. Artemis meets an elf from a fairy police force called the LEP. Artemis befriends the elf and together, with the help of other characters introduced throughout the book, they have to confront enemies such as the infamous Russian Mafia, an evil fairy named Opal Koboi, and others!
This series is highly recommend to those who are in the fourth grade reading level or higher. Although this book may be quite easy to read, everyone could enjoy it.