Acquaintance With Darkness by Ann Rinaldi
When her mother dies and her best friend's family is implicated in the assassination of President Lincoln, fourteen-year-old Emily Pigbush must go live with an uncle she suspects of being involved in stealing bodies for medical research.

Back from the Dead by Carol Gorman
After witnessing the murder of a classmate by local bullies, Julia is threatened to keep the act secret and fears telling the truth to the police, but things become more complicated when she receives a ominous note from the dead boy.

Callender Papers by Cynthia Voight
In nineteenth-century Massachusetts, orphan Jean, employed to sort out the family papers of a reclusive artist, becomes curious about the mysterious, long-ago death of his wife and the subsequent disappearance of their young child.

Dark and Deadly Pool, by Joan Lowery Nixon
Working at a luxury hotel can be more mysterious than expected, especially when bodies turn up.  Sequel: The Weekend was Murder.

Deadly Deception, by Betsy Haynes.
Ashlyn finds more than she bargained for when she attempts to solve the murder of her favorite adult.

The Disappearance: A Novel, by Rosa Guy.
Imamu Jones is the prime suspect in the disappearance of Perk, the youngest child of the people who have taken Imamu in. 

Face on the Milk Carton, Caroline Cooney.
15-year-old Janie sees a picture of her younger self, identified as a kidnapped child, on the side of a milk carton and is forced to seek the truth of her past.  Two sequels: Whatever Happened to Janie? and What Janie Found.

The Fat Man, by Maurice Gee.
Colin Potter doesn’t like Herbert Muskie from the start, and it’s not the man’s prodigious bulk or the ugly wormlike scar on his face.  It’s something much more subtle, which it seems, none of the adults around Colin can see.

Fell, by M. E. Kerr.
Fell goes to an exclusive prep school posing as someone else and finds murder and mystery.  Sequels include Fell Back and Fell Down.

Getting Lincoln’s Goat, by E.M. Goldman.
Elliot gets some experience in his planned career when he tries to solve the mystery behind the disappearance of Lincoln High School’s mascot.

I Know What You Did Last Summer by Lois Duncan.
Four teen-agers, which have desperately tried to conceal their responsibility for a hit-and-run accident, are pursued by a mystery figure seeking revenge.

Incident at Loring Groves, by Sonia Levitan.
While partying in an abandoned house with friends who are using drugs, Cassidy and Ken face a difficult decision when they find a classmate murdered and risk implicating themselves if they go to the police.

In the Middle of the Night, Robert Cormier.
When the phone rings in the middle of the night, sometimes it is better not to answer...

Killer’s Cousin, by Nancy Werlin.
After being acquitted of the murder of his girlfriend, Dan Yaffee tries to start a new life, only to find himself being harassed by his 11-year-old cousin, who may be insane.  Also try Locked Inside by Nancy Werlin.

Last Goodie, by Stephen Schwandt.
 Now that he is in high school he tries to find out what happened to his baby-sitter who disappeared when he was little.

Monster, by Walter Dean Myers.
Sixteen-year-old Steve is on trial for murder.  Is he guilty?  As the circumstances slowly unfold, readers get a chance to think carefully about the crime and serve as judge.

Music from the Dead, by Bebe Faas Rice.
Spending a week alone at creepy Stoneycraig, Marnie and her cousin Peter become increasingly alarmed at the strange sounds and unexplained events that take place, and they learn about a tragic event from sixteen years earlier.

A Place to Hide, by Robert Westall.
Lucy’s Father has a secret so dangerous that she is sent into hiding with a suitcase of money.  She must change her name, her appearance, and her entire life.

Promise Not to Tell, by Beverly Hastings.
Arriving at a small Montana ranch with a bunch of other problem teens, Julie becomes alarmed by the ranch's mysterious counselor, the back-breaking chores that are assigned to everybody, and the discovery of a dead body on the grounds.

Ruby in the Smoke, The Tiger in the Well, The Shadow in the North, by Philip Pullman.
A trilogy of mysteries set in Victorian England with Sally Lockheart, an independent young woman, as the protagonist.

The Stones of Muncaster Cathedral, by Robert Westall.
When Joe Clark gets the job of repairing Muncaster Cathedral, he is delighted, until he recognizes that there’s something amiss with the great stone gargoyle decorating the tower.

Tenderness, by Robert Cormier.
 In this disturbing psychological mystery, Eric Poole, handsome, articulate, and also deeply disturbed, is about to be released from the juvenile facility where he has spent three years for murder.  There’s no question he intends to kill again; it’s simply a matter of when.

Where It Stops, Nobody Knows, by Amy Ehrlich.
Moving from place to place with her Mother seemed like a game to Nina when she was small.  Now it seems more like hiding, and Nina wants to know why.