Mysteries in our national parks

In this fast-paced adventure, the Landons trail a wounded wolf in Yellowstone National Park. The park is abuzz with rumors of a wolf attack. Meanwhile, a killer stalks the woods. Unaware of the danger, Jack and Ashley are more concerned about rebellious teenage foster child, Troy Haverson. From the opening moments at Old Faithful through 48 action-packed hours, the tension builds: What is lodged in the wolf's radio collar? And what is the meaning

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Twelve-year-old Jack and his younger sister visit Mesa Verde National Park, where they delve into the park's history while gradually uncovering the mysterious past of their family's teenage foster child Lucky.

Grizzly cubs are disappearing from Glacier National Park, and the Landon family must figure out why! But for Jack, the real mystery is his sister Ashley's strange behavior. What was she doing alone in the woods so early in the morning? And why did she lie to their parents? Jack's efforts to unravel the truth lead to a pulse-pounding adventure that brings the Landon kids face to face with an enraged grizzly—as Jack and his sister suddenly become...

While at St. John National Park in the Virgin Islands for a seminar on coral reefs, the Landons help a wealthy thirteen-year-old to find his birth mother, who he believes is in danger.

While lost in a tunnel at Carlsbad Cavern, thirteen-year-old Jack, eleven-year-old Ashley, and their eight-year-old foster brother, Sam, think bats and darkness are their worst problems, until they stumble across thieves.

While their mother investigates a series of bear attacks in and near Gatlinburg, Tennessee, Jack and Ashley learn about country music and Cherokee people from two new friends, one of whom is keeping a secret.