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

On a field trip to the zoo, Cam Jansen uses her photographic memory to help solve what happened to Danny's lunch.

After fortifying himself with many pancakes, Nate the Great sets out to find his friend Annie's missing picture of her dog, Fang.

A fifth-grader with a photographic memory and her friend Eric help solve the mystery of the stolen diamonds.

A fifth-grader uses her photographic memory, her mother, and her friend Eric to find a missing reel of a monster film they go to see.

When Dink, Josh, and Ruth Rose visit Washington, D.C., just before Christmas, they are inadvertently caught up in a kidnapping plot that was intended for the president's dog, but also involves the president's stepdaughter and her friend Marshall.

The Alden children start out on a one-day mountain climbing excursion that becomes very exciting. They unearth some mysteries and some treasure and have a good time in the process.

The Alden children uncover a plot to sabotage the Greenfield Bears baseball team. Includes baseball puzzles and activities.

When the Alden children accompany their grandfather to the Snow Haven Lodge, a series of odd occurrences threaten to disrupt the annual winter games.

When Rosamond looks into her crystal ball to read Nate the Great's future, she sees a new case for him to solve--her money box is missing and she wants him to find it.