Here are some great titles for Third Graders:

Anderson, M. T.  Whales on Stilts (Fantasy)  Racing against the clock, shy middle-school student Lily and her best friends, Katie and Jasper, must foil the plot of her father’s conniving boss to conquer the world using an army of whales.
 
Banks, Lynn Reid  Harry the Poisonous Centipede  (Fantasy)  Harry's mother makes him promise never to go up the Up-Pipe to the world of Hoo-Mins, but Harry's best friend George has other ideas.  Sequel: Harry the Poisonous Centipede’s Big Adventure.
 
Bowen, Fred  Winners Take All  (Sports Fiction)  When Kyle fakes a catch, his baseball team goes on to win the league championship but Kyle doesn’t feel good about winning by cheating.
 
Coville, Bruce  Dragon of Doom  (Fantasy)  Moongobble, who is not a very good magician, and Edward, Moongobble’s assistant, must face the Dragon of Doom.  Other titles in the Moongobble and Me series include Weeping Werewolf and Evil Elves.
 
Duffey, Betsy  Spotlight on Cody  (Humor)  9-year-old Cody Michaels is bound for stardom in the 3rd grade talent show—just as soon as he figures out his talent.
 
Evans, Douglas  MVP*:  *Magellan Voyage Project  (Adventure)  12-year-old Adam Story is surprised but intrigued when he is challenged by the deposed ruler of Babababad to become the first kid to travel around the world in 40 days without an adult.  Adam quickly learns, however, that he has not been given ALL the details of the project.
 
Griffin, Peni  Maze  (Fantasy)  Caroline and her stepbrother enter a magic painting and find themselves trapped in a maze inhabited by dangerous mythological creatures. 
 
Gutman, Dan  Qwerty Stevens Back in Time:  The Edison Mystery  (Science Fiction)
Qwerty uses the time machine he finds in his backyard to visit Thomas Edison’s workshop in1879.
 
Hale, Bruce  Farewell My Lunchbag  (Humorous Mystery)  When 4th-grade private eye Chet Gecko is called to catch someone who is stealing food from the school cafeteria, he finds himself framed for the crime. 
                      
Hamilton, Virginia  People Could Fly  (Folklore)  African-American folktales of animals, fantasy, and the supernatural.
 
Harness, Cheryl  Ghosts of the White House  (Nonfiction)  George Washington’s ghost pulls a girl out of her school White House tour and takes her on a personal tour of the building.
 
Hirsch, Odo  Bartlett and the Ice Voyage  (Fantasy)  When an impatient queen longs to taste the delicious but fragile melidrop fruit, two explorers use “Inventiveness, Desperation, and Perseverance” to try to bring it to her.  Sequels:  Bartlett and the City of Flames, Bartlett and the Forest of Plenty.
 
Hoover, H. M.  Only Child  (Science Fiction)  On his first trip outside his spaceship home, a 12-year-old boy is kidnapped by aliens.                                 
 
King-Smith, Dick  Water Horse  (Animal fantasy)  In 1930, on the coast of Scotland, two children find a large egg which hatches into an unusual sea creature.
 
McDonald, Megan.  Stink  (Fiction) The shortest kid in the second grade, James Moody, also known as Stink, learns all about the shortest president of the United States, James Madison, when they celebrate Presidents' Day at school. 
 
Namioka, Lensey  Yang the Youngest and His Terrible Ear  (Fiction)  Yingtao is an outsider in his musical family because he is tone-deaf.  1st in a series about the family.
 
O’Connor, Jane  Emperor’s Silent Army:  Terracotta Warriors of Ancient China  (Nonfiction)  In Northern China in 1974, farmers made an incredible  archeological discovery--thousands of life-sized terracotta warrior statues.  The book tells the story of the emperor who had them created and placed near his tomb and includes remarkable photographs.
 
Reiche, Dietlof  I, Freddy  (Fantasy)  Freddy, a remarkably intelligent golden hamster, learns how to read and how to write on a computer.  Sequels:  Freddy in Peril, Freddy to the Rescue.
 
Rodda, Emily  Rowan of Rin  (Fantasy)  Reluctantly included because only he can read the magical map, young, weak, and timid Rowan joins 6 other villagers in climbing a mountain to try to restore their water supply, as fears of a dragon and other horrors threaten their progress.  1st  book in the Rowan series.
 
Scieszka, Jon  Science Verse  (Poetry)  A teacher tells his class that they can hear the poetry of science in everything.  Suddenly a student is struck with a curse and begins hearing nothing but science verses that sound very much like some well-known poems.
 
Walter, Mildred  Justin and the Best Biscuits in the World  (Fiction)  Suffering in a family of females, Justin learns real lessons in what "women's work" is when he spends time on his grandfather's ranch.?

Yep, Laurence  When the Circus Came to Town  (Historical fiction)  An Asian cook and a Chinese New Year celebrationhelp a 10-year-old girl at a Montana stage coach station to regain her confidence after smallpox scars her face.