While on bicycle trip to their aunt's farm, the four Aldens help solve a mystery.

A young Canadian visitor helps the Alden family solve a mystery involving a lost coin collection.

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 Jessies 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...

The Alden's neighbor, Lina, thinks there's treasure hidden in her attic and she wants the Boxcar Children to help her find it. Of course, the children are eager to help search—but it appears they aren't the only ones looking for the treasure.

When the Aldens visit their friend Fran in Wisconsin, they can't wait to hear her tell the story of the runaway ghost. Fran's family ghost hasn't been spotted in years, but the Aldens still shiver at the spooky tale of the ghost's bell clanging after dark. Then Violet hears a mysterious ringing in the middle of the night and the children start to wonder--could the runaway ghost be back?

While on a cruise with their grandfather, the Alden children help discover who is behind the mysterious troubles of the ship--disconnected phone lines, engine trouble, a man overboard--and still have fun sightseeing, eating, and swimming.

When the Aldens visit Yellowstone they discover a map showing the way to an old cabin where gold is supposedly hidden, but they encounter lots of interference in their attempts to hike the trail.

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.

When their grandfather arranges for them to spend two week at Sunny Oaks, the four Alden children enjoy settling into the routines of farm life but become suspicious about a mysterious horse locked in the stables.

The Alden children help out a storeowner at the Hope Harbor Mall and discover that someone is tampering with the merchandise shipments.