The Letter, the Witch, and the Ring

Rose Rita wishes she could go to camp like her best friend, Lewis. She's sure that boys get to have all the fun—until Mrs. Zimmermann offers her an adventure of her own. Mrs. Zimmermann's cousin Oley has left her his farm, as well as a ring that he thinks is magic. But when the two arrive at the deserted farm, the ring has mysteriously vanished. What power does it have? And will the person who took it use the ring to do evil?