While visiting a Navaho Indian reservation in New Mexico, the Aldens try to save a forest under threat of development by proving it is the site of a lost, buried village, but someone is sabotaging their dig.
While on a cruise with their grandfather, the Alden children help discover who is behind the mysterious troubles of the ship--disconnected phone lines, engine trouble, a man overboard--and still have fun sightseeing, eating, and swimming.
Henry, Jessie, Violet, and Benny become trapped in a cabin by an unexpected snowstorm, which turns into an even greater adventure when they help their neighbors, a baker and his family, recover an old family secret.
Six parentless kids ranging in age from 5 to 18 run away from the orphanage and, as a family, successfully establish a household miles away until local do-gooders begin investigating.
While helping their grandfather prepare for Greenfield's Winter Festival, the Alden children uncover a mystery surrounding the statue in the town square.