The Landon family travels to Glacier National Park to investigate why grizzly bear cubs are disappearing and become involved with a ten-year-old Mexican runaway boy.

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.

Life-threatening accidents keep plaguing the Landon family as they investigate the mysterious deaths of white mustangs at Zion National Park in Utah. Even before they get to the park, Jack Landon knows that Ethan Ingawanup spells trouble. Things start to go awry after Ethan and his sister--two Shoshone kids--are placed in the Landons' care. The questions begin to mount after Ethan teaches Jack and Ashley the ancient Ghost Dance: Are all the hair-raising events just coincidental? Or is there some strange magic in the dance ritual? The answers await in the raging waters of a slick-rock canyon called The Narrows. The afterword by Lyman Hafen of the Zion Natural History Association discusses white mustangs and public lands in Utah.

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.

Jack, Ashley, and their parents visit Hawaii where they meet a Vietnamese boy who is going to live with his American grandfather whom he has never met, and are pursued by the Goddess Pele.

Explores Yellowstone National Park, introducing its geography, wildlife, climate, trails, and history.

DIVWhile on vacation at a dude ranch, the Casebusters chase a horse thief/divDIV Sean and Brian Quinn can’t think of anywhere cooler than the Austin Dude Ranch. Although neither has ever ridden a horse, they’re positive that playing cowboy is going to become their favorite pastime. But before they can learn to rope and ride, they’re going to have to practice their other favorite hobby: solving mysteries./divDIV /divDIVA racehorse has been stolen from the neighboring farm, and the ranch’s owners think that their horses may be the next to disappear. To find the missing pony, Brian and Sean will have to confront something even more scary than horse thieves: the ghost of the crazy old gold prospector who is said to haunt a nearby abandoned mine. Whether the culprit is living or dead, Brian and Sean must catch him faster than they can say, “Giddy-up!”/div