At an old library, the Alden children discover a boy who needs their help and a stranger who is after a valuable object they found in the library

While canoeing and backpacking near Timberwolf Lake, the Aldens receive strange warnings to stay away from the area and stumble upon clues to a missing cache of stolen coins

The Alden children help out at the Greenfield Ice Cream Barn and while learning to make ice cream and create new flavors, they help solve a mystery before the Barn gets shut down

At the same time that the Alden children's efforts to raise money for a new hospital wing are being sabotaged by nasty tricks, they find their attempts to befriend the new girl Beth frustrated by her strange behavior

The Alden children plan to ride in their boxcar at the Greenfield Founders' Day Parade, but the newly refurbished boxcar is stolen a couple of days before the big event

"The winter sports season is here, and the Aldens are excited about all the snow activities--especially snowboarding. But soon they find themselves in the middle of a mystery surrounding a star athlete and a stolen snowboard"--

The Aldens discover there's nothing more fun than a drive-in movie. But pranks and other odd things are happening at the Diamond Drive-In, and late at night, a ghost is seen walking around the empty lot. Is the old theater really haunted?

The Aldens visit Grandfather's friend at the Ogopogo Retreat and aided by puzzling clues, embark on a treasure hunt to prevent the retreat from being sold

The Alden children investigate various mix-ups at a zoo run by their grandfather's friend in an effort to save it not only from pranksters but also from the town council

Someone is digging up sea turtle eggs! Can the Aldens find the culprit?

The Aldens are spending spring break on a beach, but they aren't just soaking up the sun. They're protecting an endangered species! Their job is to mark sea turtle nests so the eggs can be moved to a safe place to hatch, but someone is digging up the eggs without permission. Can the Boxcar Children figure out what's going on and help save the sea turtles?

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