At the request of their distant relative Althea, the Boxcar Children arrive at her old Virginia mansion and investigate the mysterious incidents happening there.
When their grandfather arranges for them to spend two weeks 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 children, snowbound in a vacation cabin, discover adventure in surrounding wild life, three children they find in the snow, and a search for a lost recipe.
Henry, Jessie, Violet, and Benny discover that some of the clues to the Great Detective Race are fake and set out to find out who is trying to ruin the race-- and why.
The Boxcar Children rush to investigate when it appears that someone is trying to rid the Ocean Adventure Park aquarium in Florida of its main attraction--a great white shark.
While visiting the seaport town of Ragged Cove, Massachusetts, the Alden children find the ship's log of the Flying Cloud, shipwrecked in 1869, supposedly during a mutiny.
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.
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 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.
The Alden children travel on a Mississippi paddle-wheel steamer to visit an old family friend in his cabin near Hannibal, Missouri, and try to discover who is responsible for the mysterious activities near the house.