The Aldens become involved in a community theater production of "The Wizard of Oz," which is systematically and mysteriously being sabotaged.

The mysterious disappearance of a reclusive neighbor's cat involves the Boxcar children in some complicated detective work.

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?

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 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.

The Boxcar children investigate when ice cream and other items start disappearing from their favorite ice cream parlor.

The Aldens, while testing the latest version of their favorite computer game, are surprised to find messages directed specifically at them.

While vacationing at a friend's country home, the four Alden siblings try to find a long-missing, priceless brooch and investigate the existence of a ghostly stream.

Benny wants adventure and finds it as he and the other Alden children help uncover the plan of those who would prevent ballooning from coming to Lloyd's Landing.

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