Middle Grade Books
Series (in some cases, the name of the series is listed, in others, just the title of the first book in the series)
Princess Academy Shannon Hale
The Unwanteds Lisa McMann
Homelanders (series) Andrew Klavan
Time Quartet (Wrinkle in Time and sequels)

Michael Vey Richard Paul Evans
Mrs. Smith's Spy School for Girls Beth McMullen
God King Joanne Williamson
A Proud Taste for Scarlet and Miniver E.L. Konisburg
The Midwife's Apprentice Karen Cushman
The Great and Terrible Quest Margaret Lovett
Salt Helen Frost
Carry On, Mr, Bowditch Jean Lee Latham
The Arrow over the Door Joseph Bruchac
Calico Bush Rachel Field
Number the Stars Lois Lowry
Once Was a Time Leila Sales
(also a time-travel book, so perhaps not strictly historical fiction!)
The Breadwinner Deborah Ellis
Mrs. Smith's Spy School for Girls Beth McMullen
Adventure
Hatchet Gary Paulsen
Holes Loius Sachar
The Last Thing I Remember Andrew Klavan
Masterminds Gordon Korman
Loot Jude Watson
Biography
Christian Heroes Series Janet Benge
Heroes of History series Janet Benge
Peace Child Don Richardson
The Hiding Place Corrie Ten Boom
Fairy Tales

You’re not too old for fairy tales! They are NOT at all like the Disney versions.
The Wise Woman and other stories George MacDonald
The Blue Fairy Book Andrew Lang
All the original fairy tales you could think of, from pretty much anywhere in the world, are in the Andrew Lang collections, but you can also look for collections of the Brothers Grimm tales, Hans Christian Andersen, Charles Perrault, or a non-Western collections of folk and fairy tales. There are many, many choices, for ALL ages.
Fairy Tale Adaptations
Cinder Marissa Meyer
Princess of the Midnight Ball (and others in the Westfalin series) Jessica Day George
The Goose Girl Shannon Hale
The Book of a Thousand Days Shannon Hale
The True Story of Jack and the Beanstalk Leisl Shurtliff Rapunzel's Revenge Shannon Hale
Valiant Sarah McGuire Fantasy/Science Fiction The Ordinary Princess M.M. Kaye
The True Story of Jack and the Beanstalk Leisl Shurtliff Rapunzel's Revenge Shannon Hale
Valiant Sarah McGuire Fantasy/Science Fiction The Ordinary Princess M.M. Kaye
Gregor the Overlander Suzanne Collins
Ranger's Apprentice John Flanagan
The Story Thieves John Riley
Saving Lucas Biggs Marisa de los Santos
A Wrinkle in Time Madeline L'Engle A Wizard of Earthsea Ursula LeGuin Historical Fiction
A Wrinkle in Time Madeline L'Engle A Wizard of Earthsea Ursula LeGuin Historical Fiction
(this category has SO many possibilities, especially for this reading level, that I can’t even get close to listing all the great options! For specific time periods or interests, ask Mrs. Meester or your local librarian for more suggestions!)
Flame Over Tara Madeleine Polland
Catherine, Called Birdy Karen Cushman
A Single Shard Linda Sue Park
The Great Wheel Robert Lawson
Little Britches Ralph Moody
Angel on the Square Gloria Whelan
The Singing Tree Kate Seredy
Esperanza Rising Pam Munoz Ryan
Esperanza Rising Pam Munoz Ryan
The Winged Watchman Hilda van Stockum
Miracles on Maple Hill Virginia Sorensen
The War That Saved My Life Kimberley Brubaker Bradley
A Long Walk to Water Linda Sue Park
Non-Fiction
The Way People Live series various authors
OR...
Get to know your Dewey Decimal system! Choose a topic you want to learn about and go find it! 
Also, you can ask Mrs. Meester or your local librarians!
Mysteries
The Westing Game Ellen Raskin
The Second Mrs. Giaconda E.L. Konisburg
Poetry
Classic Poetry (anthology) Michael Rosen (editor)
A Treasury of Poetry for Young People
National Geographic Book of Nature Poetry