A friendly writer with a metal detector, the mysterious inhabitants of a tower house, and the discovery of a locket in the sand are ingredients for the Aldens' latest mystery.

Henry, Jessie, Violet, and Benny are spending a week on a houseboat! Throughout the journey, the children have the feeling they are being watched--and they are. Someone wants something that's hidden on their boat, and they'll stop at nothing to get it.

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 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.

A family starts out on a one-day mountain climbing excursion that becomes very exciting. In fact, it becomes an adventure for the former "boxcar" family. They unearth some mysteries and have a fine time in the process.

The four Aldens take shelter in an old abandoned house during a rainstorm while on a bicycle trip to their Aunt Jane's house when a lost dog finds them.

"The Aldens are spending spring break on a beach, but they aren't just soaking up the sun. They're protecting an endangered species! Their job is to mark sea turtle nests so the eggs can be moved to a safe place to hatch, but someone is digging up the eggs without permission. Can the Boxcar Children figure out what's going on and help save the sea turtles?"--Amazon.com

Henry, Jessie, Violet, and Benny--four children who used to live alone in a boxcar and now reside with their grandfather--arrive at Camp Seagull overflowing with excitement, but they soon realize that some of the other campers are not above cheating in the annual camp Olympics.

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.

While investigating the disappearance of Spotzie, Mr. Woods's beloved cat, the Alden children discover that they are being followed by a strange man, receive threatening phone calls, and uncover a number of mysterious suspects in the catnapping. Simultaneous.