Allison, Jennifer.  Gilda Joyce:  Psychic Investigator.
During the summer before ninth grade, intrepid Gilda Joyce invites herself to the San Francisco mansion of distant cousin Lester Splinter and his thirteen-year-old daughter, where she uses her purported psychic abilities and detective skills to solve the mystery of the mansion's boarded-up tower.  J-M ALL

Balliett, Blue. Chasing Vermeer. 
When seemingly unrelated and strange events start to happen and a precious Vermeer painting disappears, eleven-year-olds Petra and Calder combine their talents to solve an international art scandal. J-M BAL

Beatty, Robert. Willa of the Wood.
In the late 1800s, a nightspirit living in the Great Smoky Mountains despairs as homesteaders destroy her forest habitat, until a chance encounter with a "day-folk" man changes everything she thought she knew about her people. J-FAN BEA

Bellairs, John.  The House With a Clock In Its Walls.
A boy goes to live with his magician uncle in a mansion that has a clock hidden in the walls which is ticking off the minutes until doomsday. J-PBK BEL

Bertram, Jennifer Chambliss. The Alcatraz Escape.
Sleuthing duo Emily and James engage in a literary escape-room challenge on Alcatraz Island, but soon find that an invisible enemy is trying to sabotage the team at any cost. J-M BER

Clements, Andrew.  Room One:  A Mystery or Two.
Ted Hammond, the only sixth grader in his small Nebraska town's one-room schoolhouse, seeks clues to the disappearance of a homeless family. J-M CLE

Colfer, Eoin. Half Moon Investigations.
Twelve-year-old private investigator Fletcher Moon, nicknamed "Half Moon" because of his shortness, must track down a conspiracy or be framed for a crime he did not commit. J-M COL

Currie, Lindsay. The Peculiar Incident on Shady Street.
When lights start flickering and temperatures suddenly drop, twelve-year-old Tessa Woodward, sensing her new house may be haunted, recruits some new friends to help her unravel the mystery of who or what is trying to communicate with her and why. J CUR

Funke, Cornelia.  The Thief Lord.
Two brothers, having run away from the aunt who plans to adopt the younger one, are sought by a detective hired by their aunt, but they have found shelter with Venice's "Thief Lord." J FUN, J-PBK FUN

Grabenstein, Chris. Escape from Mr. Lemoncello's Library.
Twelve-year-old Kyle gets to stay overnight in the new town library, designed by his hero (the famous gamemaker Luigi Lemoncello), with other students but finds that come morning he must work with friends to solve puzzles in order to escape. J GRA

Hahn, Mary Downing.  The Dead Man in Indian Creek.
When Matt and Parker learn the body they found in Indian Creek is a drug-related death, they fear Parkers' mother may be involved. J-PBK HAH

Howe, Deborah. Bunnicula: A Rabbit Tale of Mystery. 
Though scoffed at by Harold the dog, Chester the cat tries to warn his human family that their foundling baby bunny must be a vampire. J-M HOW, J-PBK HOW

Johnson, Varian. The Great Greene Heist.
Jackson Greene has a reputation as a prankster at Maplewood Middle School, but after the last disaster he is trying to go straight--but when it looks like Keith Sinclair may steal the election for school president from Jackson's former best friend Gabriela, he assembles a team to make sure Keith does not succeed. J JOH

Kane, Karen. Charlie and Frog: A Mystery.
While staying with his grandparents in Castle-on-the-Hudson, Charlie stumbles upon a mystery but must learn American Sign Language to keep up with Frog, a deaf girl who wants to help solve it. J-M KAN

Klause, Annette Curtis.  Alien Secrets.
On her journey to the distant planet where her parents are working, twelve-year-old Puck befriends a troubled alien and becomes involved in a dangerous mystery involving a precious artifact. J-SF KLA  

Lisle, Janet Taylor.  Black Duck.
Years afterwards, Ruben Hart tells the story of how, in 1929 Newport, his and his best friend's families were caught up in the violent competition among groups trying to control the local rum-smuggling trade. J-HF LIS  

Mack, Tracy.  The Fall of the Amazing Zalindas.
The ragamuffin boys known as the Baker Street Irregulars help Sherlock Holmes solve the mysterious deaths of a family of circus tightrope walkers. J-M MAC

Nickerson, Sara. How to Disappear Completely and Never Be Found.
With a swimming medal, the key to a mansion, and a comic book about a half-man/half-rat as her only clues, a twelve-year-old girl seeks the true story of her father's mysterious death four years earlier near an island in the Pacific Northwest. J-M NIC    

Ponti, James. Framed! A T.O.A.S.T. Mystery.
In Washington, D.C., twelve-year-old Florian Bates, a consulting detective for the FBI, and his best friend Margaret help thwart the biggest art heist in United States history. J-M PON

Raskin, Ellen. The Westing Game. 
The mysterious death of an eccentric millionaire brings together an unlikely assortment of heirs who must uncover the circumstances of his death before they can claim their inheritance. J-M RAS, J-PBK RAS

Ruby, Laura. The Shadow Cipher.
First in York: an epic alternate history series about three kids who try to solve the greatest mystery of the modern world: a puzzle and treasure hunt laid into the very streets and buildings of New York City. J-M RUB

Springer, Nancy. The Case of the Missing Marquess.
When Enola Holmes, sister to the detective Sherlock Holmes, discovers her mother has disappeared, she quickly embarks on a journey to London in search of her. When she arrives, she finds herself involved in the kidnapping of a young marquess, fleeing murderous villains, and trying to elude her shrewd older brothers. J M SPR

Stead, Rebecca. When You Reach Me.
As her mother prepares to be a contestant on the 1980s television game show, "The $20,000 Pyramid," a twelve-year-old New York City girl tries to make sense of a series of mysterious notes received from an anonymous source that seems to defy the laws of time and space. J STE

Teele, Elinor. The Treasure of Mad Doc Magee.
When her father loses his job, Jenny Burns and her best friend Pandora search for Mad Doc Magee's hidden gold nugget, a journey filled with dangers, riddles, and mysteries. J-HF TEE

Tubb, Kristin O'Donnell. The Story Collector.
A fictional account of eleven-year-old Viviani Joffre Fedeler, who was born and raised in the New York Public Library, and her older brothers and best friend Eva, who all try and find out if the library is haunted. J-M TUB