If you’re looking for some of the best middle-grade mystery books for your wanna-be detective tween, stick around! I rounded up my top picks below. Most of them are relatively new releases (published within the last year), but I threw in a few “oldies-but-goodies” that I really think tweens will love. Let’s check them out, shall we?
Top 20 Best Mystery Books for Tweens
As always, before we get started I have a couple of very quick notes. First, whenever possible I’ve included the Kindle book preview for you (not all books have that option). That way, you can check out a sample without leaving this page.
Second, when the book is part of a series, I’ll mention that and use the first one even if it’s not the most recent. I just think that makes things easier. That way, you’re not buying book 50 when your kid hasn’t read 1-49. 😀
Last, this post uses affiliate links. If you buy anything through them, I’ll earn a small commission at no extra cost to you. That about covers it. Now let’s get started!
1. Charlie Thorne and the Last Equation (Charlie Thorne Series)
The Charlie Thorne series is perfect for tweens who love adventure mysteries. Think Dan Brown style, but for a younger audience. This is the first in a 3-book (so far) series. The 3rd one, the Curse of Cleopatra, just came out this month.
Charlie Thorne is a genius.
Charlie Thorne is a thief.
Charlie Thorne isn’t old enough to drive.
And now it’s up to her to save the world…
Decades ago, Albert Einstein devised an equation that could benefit all life on earth—or destroy it. Fearing what would happen if the equation fell into the wrong hands, he hid it.
But now, a diabolical group known as the Furies are closing in on its location. In desperation, a team of CIA agents drags Charlie into the hunt, needing her brilliance to find it first—even though this means placing her life in grave danger.
In a breakneck adventure that spans the globe, Charlie must crack a complex code created by Einstein himself, struggle to survive in a world where no one can be trusted, and fight to keep the last equation safe once and for all.
2. Spy School (Spy School Series)
Another awesome middle-grade mystery series from Stuart Gibbs, Spy School just released its 10th tome, Spy School Project X. So if your kids enjoy this first one, they’ll have plenty more to keep them reading all summer long!
Like many kids, Ben Ripley imagines life as a secret agent would be pretty awesome — so when he learns he’s been recruited to the C.I.A.’s top secret Academy of Espionage, it sounds too good to be true. And it is.
From the moment he arrives — and ends up in the middle of an enemy attack — Ben finds Spy School is going to be far more difficult, dastardly and dangerous than he expected. Even worse, he soon discovers that he hasn’t been recruited to become a top agent; instead, he’s been brought in as bait to catch a devious double agent.
Now, Ben needs a crash course in espionage so that he can catch the mole, prove his worth — and get the girl. It won’t be easy, but it’ll be a very fun — and very funny — ride.
Escape is perfect for tweens who want their mystery hidden beneath layers of action and adventure.
WESTWORLD meets CHARLIE AND THE CHOCOLATE FACTORY meets JURASSIC PARK, as kids win a chance to enter the place of their dreams — and find that it quickly turns into a nightmare.
It’s all anyone talks about, and it’s all Cody dreams about. It’s the biggest adventure park in the world, and it’s more than mere rides and rollercoasters: At ESCAPE, you can do anything you want, be anyone you want, and there are no adults to tell you no.
Cody’s a nobody, but for some reason, he receives an invitation and the opportunity of a lifetime. At first, it’s the most fun he’s ever had. But after a few days, everything in the park starts to go haywire. One at a time, rides malfunction. Simulations turn deadly. His fantasy world glitches and the games become races for survival. A voice comes over the intercoms, then-ESCAPE was never a theme park for the rich and famous. It was a place for punishment. They have less than a week to escape from the park before it floods. Only five kids will be allowed to leave.
It started out as a fight to get to the coolest rides. Now, they have to fight to survive.
4. The Mysterious Benedict Society (Series)
The Mysterious Benedict Society, one of the most highly-rated middle-grade mystery series, is perfect for fans of books like A Series of Unfortunate Events. There are currently 4 books out, plus a prequel. It’s also a series on Disney+!
“Are you a gifted child looking for special opportunities?” Dozens of children respond to this peculiar ad in the newspaper and are then put through a series of mind-bending tests, which readers take along with them. Only four children–two boys and two girls–succeed. Their challenge: to go on a secret mission that only the most intelligent and inventive children could complete. To accomplish it they will have to go undercover at the Learning Institute for the Very Enlightened, where the only rule is that there are no rules. But what they’ll find in the hidden underground tunnels of the school is more than your average school supplies. So, if you’re gifted, creative, or happen to know Morse Code, they could probably use your help.
5. Wretched Waterpark (The Sinister Summer Series)
I’ve been a huge fan of Kiersten White ever since her YA Paranormalcy series. I had no idea that she was writing tween books now, too! There are only two books out in this series so far, but they look fantastic! Perfect for tweens who like their mysteries with a side of spookiness.
Meet the Sinister-Winterbottoms: brave Theo, her timid twin, Alexander, and their older sister, Wil. They’re stuck for the summer with their Aunt Saffronia, who doesn’t know how often children need to eat and can’t use a smartphone, and whose feet never quite seem to touch the floor when she glides—er—walks.
When Aunt Saffronia suggests a week pass to the Fathoms of Fun Waterpark, they hastily agree. But the park is even stranger than Aunt Saffronia. The waterslides look like gray gargoyle tongues. The employees wear creepy black dresses and deliver ominous messages. An impossible figure is at the top of the slide tower, people are disappearing, and suspicious goo is seeping into the wave pool.
Something mysterious is happening at Fathoms of Fun, and it’s up to the twins to get to the bottom of it. The mystery, that is. NOT the wave pool. Definitely NOT the wave pool. But are Theo and Alexander out of their depth?
6. Nancy Drew (All New) Girl Detective Series
We can’t really talk about middle-grade mystery books without mentioning Nancy Drew, now can we? There are close to 200 books in the original series, plus several more modern versions (like the one previewed here).
Hi, I’m Nancy Drew, and I’ve got a case to crack. Actually make that two cases. First a gorgeous Fabergé egg has been stolen. Who would have the heart to snatch such a precious family heirloom from someone new to town? Some housewarming that is!
And if this isn’t enough to keep me busy, someone’s running through gardens and stomping on all the zucchinis. Needless to say, it’s a big mess — in more ways than one. Especially for Mr. Safer, who is suspected of squishing the squash. I’m pretty sure Mr. Safer’s innocent. But who’s the real vegetable vandal?
7. Shadow Jumper (A Shadow Jumper Mystery Adventure)
Currently, there are two books in the Shadow Jumper series. Both of them are free on Kindle Unlimited. 😀
The truth is out there somewhere . . . but how far is Jack willing to jump to find it? Jack Phillips’s allergy to sunshine confines him to the shadows, leaving him lonely and at risk of life-threatening burns every time he steps into the light. Shadow jumping on the rooftops at dusk makes him feel alive. And free.
But Jack’s condition is suddenly worse than ever and only his missing scientist dad can save him. As Jack and his new friend, Beth, begin their frantic search and delve into his dad’s past for clues, they have no idea what they are about to uncover. Shocking rumours and dark secrets bombard them at every turn. Jack is brave on the roofs. But can he find the courage to face the truth?
8. Greenglass House
FYI, this one is available for free if you subscribe to Amazon Kids. If they enjoy the gothic-throwback novel, there are 4 more in the series. All are standalone mysteries.
It’s wintertime at Greenglass House. The creaky smuggler’s inn is always quiet during this season, and twelve-year-old Milo, the innkeepers’ adopted son, plans to spend his holidays relaxing.
But on the first icy night of vacation, out of nowhere, the guest bell rings. Then rings again. And again…
Soon Milo’s home is bursting with odd, secretive guests, each one bearing a strange story that is somehow connected to the rambling old house. As objects go missing and tempers flare, Milo and Meddy, the cook’s daughter, must decipher clues and untangle the web of deepening mysteries to discover the truth about Greenglass House—and themselves.
9. The Westing Game
Like Nancy Drew, The Westing Game is a classic that every mystery-lover should read at least once. It won the Newberry Medal award back in 1978 (the year it was released). In 2020, HBO announced that it was developing the book into a series, but I’m not sure where they’re at with that.
A bizarre chain of events begins when sixteen unlikely people gather for the reading of Samuel W. Westing’s will. And though no one knows why the eccentric, game-loving millionaire has chosen a virtual stranger—and a possible murderer—to inherit his vast fortune, one thing’s for sure: Sam Westing may be dead…but that won’t stop him from playing one last game!
10. Book Scavenger
Book Scavenger follows the adventures of 12-year-old Emily and her new friends as they race to follow clues and find out what happened to their favorite writer. It’s the first in a 3-book series. Check out all three titles below:
For twelve-year-old Emily, the best thing about moving to San Francisco is that it’s the home city of her literary idol: Garrison Griswold, book publisher and creator of the online sensation Book Scavenger (a game where books are hidden in cities all over the country and clues to find them are revealed through puzzles).
Upon her arrival, however, Emily learns that Griswold has been attacked and is now in a coma, and no one knows anything about the epic new game he had been poised to launch. Then Emily and her new friend James discover an odd book, which they come to believe is from Griswold himself, and might contain the only copy of his mysterious new game.
Racing against time, Emily and James rush from clue to clue, desperate to figure out the secret at the heart of Griswold’s new game—before those who attacked Griswold come after them too.
11. From the Mixed-Up Files of Mrs. Basil E. Frankweiler
Not only is this one a two-time Newberry Medal Winner, but it’s also one of Time magazine’s best YA Books of All Time. That’s quite an accomplishment considering other novels include classics like The Diary of Anne Frank and Little Women!
When Claudia decided to run away, she planned very carefully. She would be gone just long enough to teach her parents a lesson in Claudia appreciation. And she would go in comfort – she would live at the Metropolitan Museum of Art. She saved her money, and she invited her brother Jamie to go, mostly because he was a miser and would have money.
Claudia was a good organizer and Jamie had some ideas, too; so the two took up residence at the museum right on schedule. But once the fun of settling in was over, Claudia had two unexpected problems: She felt just the same, and she wanted to feel different, and she found a statue at the Museum so beautiful she could not go home until she had discovered its maker, a question that baffled the experts, too. Literally!
12. Chasing Vermeer
When a book of unexplainable occurrences brings Petra and Calder together, strange things start to happen: Seemingly unrelated events connect; an eccentric old woman seeks their company; an invaluable Vermeer painting disappears. Before they know it, the two find themselves at the center of an international art scandal, where no one is spared from suspicion. As Petra and Calder are drawn clue by clue into a mysterious labyrinth, they must draw on their powers of intuition, their problem-solving skills, and their knowledge of Vermeer. Can they decipher a crime that has stumped even the FBI?
This one has it all: mystery, intrigue, action, adventure, and the incredible bond of friendship! If your tweens love it, Ponti has a bunch of other books that they may enjoy, too (including two more in this series). Check out a few of them below.
So you’re only halfway through your homework and the Director of the FBI keeps texting you for help…What do you do? Save your grade? Or save the country?
If you’re Florian Bates, you figure out a way to do both.
Florian is twelve years old and has just moved to Washington. He’s learning his way around using TOAST, which stands for the Theory of All Small Things. It’s a technique he invented to solve life’s little mysteries such as: where to sit on the first day of school, or which Chinese restaurant has the best eggrolls.
But when he teaches it to his new friend Margaret, they uncover a mystery that isn’t little. In fact, it’s HUGE, and it involves the National Gallery, the FBI, and a notorious crime syndicate known as EEL.
Can Florian decipher the clues and finish his homework in time to help the FBI solve the case?
14. The Strangers (The Greystone Secrets #1)
This one is also available free on Amazon Kids, as is the second book in the series. The 3rd book in the trilogy is out, but it’s not free yet.
The Greystone kids thought they knew. Chess has always been the protector over his younger siblings, Emma loves math, and Finn does what Finn does best—acting silly and being adored. They’ve been a happy family, just the three of them and their mom.
But everything changes when reports of three kidnapped children reach the Greystone kids, and they’re shocked by the startling similarities between themselves and these complete strangers. The other kids share their same first and middle names. They’re the same ages. They even have identical birthdays. Who, exactly, are these strangers?
Before Chess, Emma, and Finn can question their mom about it, she takes off on a sudden work trip and leaves them in the care of Ms. Morales and her daughter, Natalie. But puzzling clues left behind lead to complex codes, hidden rooms, and a dangerous secret that will turn their world upside down.
15. The Screaming Staircase (Lockwood & Co., #1)
The 5-book Lockwood & Co. series is perfect for tweens that want a little magic mixed in with their mysteries. If you read Strouds’s popular Bartimaeus Sequence series, you know he’s such an expert at crafting rich and imaginative worlds!
In The Screaming Staircase, the plucky and talented Lucy Carlyle teams up with Anthony Lockwood, the charismatic leader of Lockwood & Co, a small agency that runs independently of any adult supervision. After an assignment leads to both a grisly discovery and a disastrous end, Lucy, Anthony, and their sarcastic colleague, George, are forced to take part in the perilous investigation of Combe Carey Hall, one of the most haunted houses in England. Will Lockwood & Co. survive the Hall’s legendary Screaming Staircase and Red Room to see another day?
16. Under the Egg
If your tweens loved From the Mixed-Up Files of Mrs. Basil E. Frankweiler, they’ll adore this one by the same author.
When Theodora Tenpenny spills a bottle of rubbing alcohol on her late grandfather’s painting, she discovers what seems to be an old Renaissance masterpiece underneath. That’s great news for Theo, who’s struggling to hang onto her family’s two-hundred-year-old townhouse and support her unstable mother on her grandfather’s legacy of $463. There’s just one problem: Theo’s grandfather was a security guard at the Metropolitan Museum of Art, and she worries the painting may be stolen.
With the help of some unusual new friends, Theo’s search for answers takes her all around Manhattan, and introduces her to a side of the city—and her grandfather—that she never knew. To solve the mystery, she’ll have to abandon her hard-won self-reliance and build a community, one serendipitous friendship at a time.
17. The Case of the Missing Marquess (Enola Holmes, #1)
I loved the Enola Holmes movies on Netflix, and I heard the books are even better! Isn’t that always the case, though? There are 6 out now, and the last one came out this year. So there may be more to come!
Meet Enola Holmes, a teenage girl turned detective and the younger sister to Sherlock Holmes.
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. But nothing can prepare her for what awaits. Because 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—all while attempting to piece together clues to her mother’s strange disappearance. Amid all the mayhem, will Enola be able to decode the necessary clues and find her mother?
18. The Mystery of Black Hollow Lane
This one is free for Kindle Unlimited subscribers.
With a dad who disappeared years ago and a mother who’s a bit too busy to parent, Emmy is shipped off to Wellsworth, a prestigious boarding school in England, where she’s sure she won’t fit in.
But then she finds a box of mysterious medallions in the attic of her home with a note reading: These belonged to your father.
When she arrives at school, she finds the strange symbols from the medallions etched into walls and books, which leads Emmy and her new friends, Jack and Lola, to Wellsworth’s secret society: The Order of Black Hollow Lane.
Emmy can’t help but think that the society had something to do with her dad’s disappearance, and that there may be more than just dark secrets in the halls of Wellsworth…
19. Theodore Boone: Kid Lawyer
Did you know that John Grisham wrote a middle-grade mystery series, too? Pretty neat, huh? There are 7 books in the series, so it should keep your tweens busy for a while.
The thrilling young mystery series from internationally bestselling author John Grisham!
In the small city of Strattenburg, there are many lawyers, and though he’s only thirteen years old, Theo Boone thinks he’s one of them. Theo knows every judge, policeman, court clerk—and a lot about the law. He dreams of being a great trial lawyer, of a life in the courtroom.
But Theo finds himself in court much sooner than expected. Because he knows so much—maybe too much—he is suddenly dragged into the middle of a sensational murder trial. A cold-blooded killer is about to go free, and only Theo knows the truth.
The stakes are high, but Theo won’t stop until justice is served.
20. The Mysterious Howling (The Incorrigible Children of Ashton Place #1)
There are 6 books in this series, and you can read the first one for free on Amazon Kids. It’s a great mystery series for younger middle-graders (ages 8+)
Found running wild in the forest of Ashton Place, the Incorrigibles are no ordinary children: Alexander, age ten or thereabouts, keeps his siblings in line with gentle nips; Cassiopeia, perhaps four or five, has a bark that is (usually) worse than her bite; and Beowulf, age somewhere-in-the-middle, is alarmingly adept at chasing squirrels.
Luckily, Miss Penelope Lumley is no ordinary governess. Only fifteen years old and a recent graduate of the Swanburne Academy for Poor Bright Females, Penelope embraces the challenge of her new position. Though she is eager to instruct the children in Latin verbs and the proper use of globes, first she must help them overcome their canine tendencies.
But mysteries abound at Ashton Place: Who are these three wild creatures, and how did they come to live in the vast forests of the estate? Why does Old Timothy, the coachman, lurk around every corner? Will Penelope be able to teach the Incorrigibles table manners and socially useful phrases in time for Lady Constance’s holiday ball? And what on earth is a schottische?
More wonderful Tween mystery books to consider
While the 20 books and series above are definitely my top picks for the best tween mystery books, there are a bunch more that deserve a mention here.
I’m going to keep this section short and sweet, though, to keep this from getting out of control. 😀 The links take you directly to the Amazon page for each book so you can read more about them. I also noted how many books there are in the series where applicable.
- Gilda Joyce: Psychic Investigator by Jennifer Allison (1st in a 5-book series)
- The Van Gogh Deception by Deron R. Hicks (3 books total)
- The Shadow Cipher by Laura Ruby (York, #1 of 3 books)
- Nick and Tesla’s High-Voltage Danger Lab: A Mystery with Electromagnets, Burglar Alarms, and Other Gadgets You Can Build Yourself by Bob Pflugfelder (5 books)
- The Thieves of Ostia by Caroline Lawrence (Roman Mysteries, #1 of 17)
- The Detective’s Assistant by Kate Hannigan
- Eye of the Crow by Shane Peacock (The Boy Sherlock Holmes, #1 of 6)
- Black Cats and Butlers by Janine Beacham (Rose Raventhorpe Investigates, #1 of 3)
- Midnight at the Barclay Hotel by Fleur Bradley
- The Ambrose Deception by Emily Ecton
- The Dare: Friends, Family, and Other Eerie Mysteries by Cynthea Liu
- The Fall of the Amazing Zalindas by Tracy Mack (Sherlock Holmes and the Baker Street Irregulars #1 of 4)
- Walls Within Walls by Maureen Sherry
- Space Case by Stuart Gibbs (Moon Base Alpha, #1 of 3)
- Who Could That Be at This Hour? by Lemony Snicket (All the Wrong Questions, #1 of 4)
I hope you enjoyed this list and found a few good tween mystery books for your middle graders!
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