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.

The Alden children discover another mystery when the agree to help injured Mr. Yee tend to his plot in the community garden and find out that vegetables are going missing and plots are being vandalized.

Two brothers take summer jobs at a department store where a series of peculiar events brings them under suspicion.

The Boxcar Children have been choosen to compete against another team to look for clues on a game show.

Someone is trying to put Aunt Jane's motel out of business, but the Alden children aren't going to let that happen.

While on a camping trip with their grandfather, the Alden children try to find out about the loud music and missing food that threatens to scare away other campers.

The Alden family rents a houseboat to drift down the river, and encounters a mystery in the little towns along the river, involving a fast black car.

Black cats? Broken mirrors? The number thirteen? The owner of the art deco apartment building in nearby Silver City believes in all kinds of superstitions. The Aldens aren't so sure about most of them, but there's one thing they do know: something strange is going on on the thirteenth floor. Are they just coincidences, or is the building manager onto something?

Henry, Jessie, Violet, and Benny become trapped in a cabin by an unexpected snowstorm, which turns into an even greater adventure when they help their neighbors, a baker and his family, recover an old family secret.

While helping run Jerry Taylor's general store, the Alden children investigate his mysterious employee Nancy.