The Aldens are spending a week at Camp Seagull on beautiful Claw Island. But as soon as camp begins, they realize that someone is not playing fair. Everything begins to go wrong for the Aldens—they lose their luggage, Henry misplaces the camp flag, and the campers on the other team use one of Jessie's ideas to score points for themselves. Are some campers so desperate to win the Olympics that they are willing to cheat? The Boxcar Children are determined to solve the mystery before the competition is ruined for everyone!

Henry, Jessie, Violet, and Benny used to live alone in a boxcar. Now they have a home with their grandfather, and they're fixing up the old Bugbee House, a spooky mansion in their neighborhood!   The Aldens are helping the Heart and Hands group restore an old estate. The house is bursting with collections of its mysterious and eccentric former owner. But when the contents of the house are auctioned off, the Aldens discover that much of the collection is missing! And that's not the only mystery awaiting the Aldens in this strange mansion. As the children explore, they come across hidden rooms, secret passageways, and strange noises coming from the walls. The Aldens are determined to learn the secret of the Bugbee house . . . but are they the only ones?

Henry, Jessie, Violet, and Benny used to live alone in a boxcar. Now they have a home with their grandfather, and they're going to a comic book convention!   The Alden Children are searching for a rare comic book of their favorite superhero, Captain Fantastic. When they finally find the comic, they discover something else, too: a strange note inside, "signed" by the comic's creator. The Aldens soon realize the note is fake. But when they start to investigate, the mysterious note is stolen! It looks like Captain Fantastic has a real-life enemy. Who would want to sabotage a superhero? The Aldens will need their super powers of investigation to catch this comic book culprit!

Henry, Jessie, Violet, and Benny used to live alone in a boxcar. Now they have a home with their grandfather, and they've received an invitation to a mystery!   When their friend Sam gets a letter full of riddles from an eccentric millionaire, the Aldens are eager to help him crack the code. If Sam can solve the puzzle in time, he will inherit the millionaire's money! But Sam isn't the only one in town to receive such a letter—and whoever solves the mystery first will win the prize. The Aldens are eager to help their friend, but solving the millionaire's mystery turns out to be even harder than they expected. When every clue eventually leads them back to Sam, the Boxcar Children begin to wonder: Could the answer lie somewhere in Sam's mysterious past?

 It's a big week at Cogwheel Stadium—the Clayton Cogs are playing for the pennant! But the other team's batters seem to know the pitches too well, and it's clear someone in the stadium is stealing the Cogs' pitcher's signals. Now the Boxcar Children must find out who is spying for the other team!

The Alden children go on a classic Mississippi steamboat to visit a family friend in Missouri, there they have to uncover who is responsible for the mysterious happenings near the cabin.

When Grandfather's friend bought Skeleton Point, she invited the Alden children to help her fix it up. But this empty mansion is even spookier than it looks. The man who used to live there studied bones—and the house it filled with skeletons! Then the mansions valuable statues begin to disappear. Could the Skeleton Point ghost be causing mischief?

Henry, Jessie, Violet, and Benny used to live alone in a boxcar. Now they have a home with their grandfather and a new computer to play games on!   During a visit to a computer game company, the Aldens meet the designers of their favorite game: Ringmaster. When the designers learn the Aldens are Ringmaster experts, they ask for their help. Would the Aldens test the new version of the game before it is sent out to stores? The Aldens gladly agree. But soon, the characters in Ringmaster II are giving the Aldens strange clues about people and places in real life! Is someone using the computer game to tell them something is wrong? The Boxcar Children are determined to find out!

 When a dog training school opens in Greenfield, the Boxcar Children bring Watch in to learn some new tricks! But at the very first class, a Dalmatian goes missing—did the dog run away, or was he stolen? And when a second dog vanishes at the next class, it's clear that the Aldens have a dog-gone mystery to solve!

Henry, Jessie, Violet, and Benny used to live alone in a boxcar. Now they have a home with their grandfather, and they're going to visit his old school with him!   The Aldens are spending a weekend at Goldwin University for Grandfather's college reunion. The Alden children are immediately fascinated by the tall, mysterious clock tower that overshadowed the campus. They soon learn the valuable secret from the past lies hidden somewhere at the old school—and they think the clock tower might hold the key to discovering it! But there are strange lights coming form the clock tower at night. Is the tower haunted by ghosts of the past? Or is someone else searching for the secret of Goldwin University? The Boxcar Children are convinced that someone at the school is not what he or she seems—and they are determined to find out who it is!

The Boxcar Children are investigating strange events at a hotel that some people say is haunted, and it seems like every room holds a new surprise. In this interactive, choose-your-path mystery, readers will put their sleuthing skills to the test, making decisions that will either help the Aldens crack the case or lead them deeper into the haunted hotel.

 The Aldens are helping out at a rescue ranch, taking care of horses that need extra attention. Jessie's favorite is a beautiful horse named Dragon. But when Dragon and some of the other horses disappear from the pasture, the Boxcar Children must saddle up for a mystery. What's happening to the horses at the Dare to Dream Ranch?

The Aldens are visiting the New Jersey shore and enjoying the beach and the boardwalk attractions. A family friend has just bought an amusement pier, and the children are excited to help out. But there are rumors that the rides aren't safe, and someone has stolen a zombie from the haunted house! Can the Boxcar Children find out what's behind all the trouble?

When the Boxcar Children uncover a strange puzzle in a friend's backyard, it's just the beginning of the "spy game"—a search for clues leading to gold! The children must make sense of a mysterious old photo and a riddle. But soon the children begin to suspect that there's a mystery inside the mystery. Just who is behind this spy game, anyway?

The Aldens are helping Greenfield's most popular band get ready for a music festival. A big-time music producer will be there to watch the show, and everyone in Greenfield is hoping the band will be famous soon. The day before the festival, the band's instruments are stolen! Can the Aldens find the instruments—and the thief—before the big show?