The Aldens try to solve a series of mysteries which took place in a old hotel in Kansas which they visit.

"The Aldens are spending their first week of summer at Camp Quest in Colorado. The children are excited to learn about fossil hunting and paleontology from renowned scientist Dr. Iris Perez. But strange events at the camp make them wonder if the legends of a bigfoot-like creature roaming the valley might be more fact than fiction. Can the Aldens help Dr. Iris figure out who - or what - is causing such a stir?"--Amazon.

"The Aldens have joined Dr. Iris Perez as she investigates legendary creatures around the world. In this adventure, the children travel to Iceland to look into stories of mischievous elves causing trouble. The legends of huldufolk, or hidden people, go back a long way in the country, but are elves really the cause of the problems, or is there a more natural explanation for the strange events on the island?"--Amazon.

The Aldens investigate when a new store called the Game Spot opens in town and the neighboring shops are robbed.

In The ghost of the chattering bones, 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. In The creature in Ogopogo Lake, the Aldens visit Grandfather's friend at the Ogopogo Retreat and aided by puzzling clues, embark on a treasure hunt to prevent the retreat from being sold. In The vampire mystery, when the Aldens agree to watch the...

When the Boxcar children help out in a local garden, they dig up one strange thing after another! First, the tomato plants seem to move every day. Find out how that can be.

On the train tour, the Aldens are learning all about the cowboy ways of the Old West. But someone is bringing the lawless ways of a bandit to life too! Can you help the children catch the culprit before the end of the line?

Three adventures of the Alden children, who once lived on their own in a boxcar.

The Aldens visit Grandfather's friend at the Ogopogo Retreat and aided by puzzling clues, embark on a treasure hunt to prevent the retreat from being sold.

The Aldens are visiting friends for a big Dia de los Muertos celebration. The kids love learning about the holiday and helping out - that is until mysterious events threaten to ruin everyone's preparations. Can the Aldens figure out what's going on and help their friends save the celebration?