One of my favorite books when I was a kid was High Elk's Treasure, by Virginia Driving Hawk Sneve (New York : Holiday House, 1972). High Elk's Treasure is about the High Elk family, a Dakota family with a proud history of raising the best horses on the plains. Now, there are only a few horses left of the stock that their forebears bred, and Joe High Elk, the 13-year-old son, wants to re-establish the line with the last remaining filly. A sudden storm blows up, endangering the filly, but providing for an astonishing insight into the family's history.
One of my other favorites was Ghost Paddle: A Northwest Coast Indian Tale, by James Houston (New York : Harcourt Brace Jovanovich, 1972). Ghost Paddle is about an ongoing war between two Pacific Coast tribes, and a dream that provides the key to peace between them. The story is well told, and the illustrations are lovely, leading to a lifelong interest for me in Pacific Coast aboriginal art.