The paperback editions of The Boxcar Children Mysteries: #1, The Boxcar Children; #2, Surprise Island; #3, The Yellow House Mystery; and #4, Mystery Ranch are offered together in a cardboard case.

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

It's summertime, and Henry and Benny are excited about their new jobs in the local department store. When a valuable vase disappears, the manager suspects the boys of causing trouble. They're innocent, but who is responsible for all the suspicious things going on? It's up to Benny to uncover the mystery. . . .

"The Animal Shelter Mystery: "When a calico cat appears at Grandfather's, the children look for the founder of the town's animal shelter.
"The Old Motel Mystery: "The Boxcar Children offer to help Aunt Jane's friend, Kay, fix up her run-down motel.
"The Mystery of the Hidden Painting: "The discovery of a painting of the children's grandmother involves the Aldens in a search for a sapphire necklace.

The Greenfield Museum is holding a special exhibit about ancient Egypt, and the main attraction is a 4,000-year-old mummy. The Aldens are helping the museum curator set up the exhibit and learning about life in ancient Egypt. But the longer the Aldens are around the mummy, the more things go wrong. As the children search for the cause of all the bad luck, everything points back to the spooky sarcophagus. Has the museum been struck by a curse from the ancient mummy?

The Aldens start a business producing birthday parties and find themselves investigating a series of robberies taking place during their parties.