by Wendelin Van Draanen (2010)
When her history teacher begins receiving death threats and her own name is near the top of the suspect list, eighth-grader Sammy is determined to find the real perpetrator, but she is distracted by her mother's relationship problems, her almost-boyfriend inexplicably avoiding her, and her duties as a reluctant bridesmaid.
Melissa Kantor
When new and unconventional high school student Amada Valentino disappears, her three closest friends, who are all from vastly different circles, band together and, using enigmatic clues that seem to come from Amanda herself, try to find her.
N. Griffin
There's never a dull moment in Room 11. Smashie McPerter and her best friend, Dontel Marquise, are thrilled that their class and other third-graders will be participating in a performance to showcase their talents to their families and friends. Smashie desperately wants to sing, but is seems her teacher and classmates are determined to steer her in another, non-vocal direction. Smashie's hurt feelings are put to one side, however, as she and Dontel become caught up in an intriguing mystery. A jar of hair goop, vital to the success of a performance, goes missing under suspicious circumstances., and the two friends decide to don their Investigation Suits. But although they have a knack for solving mysteries through hard work and determination, their sleuthing doesn't always go over well with their classmates. Can they find the good stealer and mend fences before chaos brakes loose? --
Helen Wells
When Cherry goes to work as the nurse at a chateau-turned-boarding school, she and one of the students discover a formula that, when constituted to its exact specifications, produces a perfume that saves the school from bankruptcy.
Franklin W. Dixon
Frank and Joe Hardy are called upon to find a wealthy industrialists's son who has mysteriously disappeared. Did Graham Retson flee from his home because he was at odds with his father, or was he kidnapped? Finding the answer turns into something more dangerous and larger in scope than Frank and Joe ever bargained for. The only clue in the case leads the two young detectives to South America, where the intrigues of evil adversaries almost cost them their lives. Involved in this complex mystery are a fierce-looking monkey trained to be a killer, a school of voracious, man-eating piranhas, a ruthless gang of passport thieves, and a cleverly operated change-your-identity mill for criminals. Only through their courage and perseverance do the Hardys solve one of the toughest cases they have ever tackled. - Flyleaf.