Place sweet potatoes in a Dutch oven or large kettle and cover with water. Bring to a boil. Reduce heat; cover and simmer for 30-45 minutes or until tender. Drain; cool slightly. Peel and cut each potato lengthwise into quarters; cut each quarter into two or three wedges. Place in a greased 13-in. x 9-in. baking dish.
Drain pineapple, reserving juice. Sprinkle pineapple over potatoes. In a saucepan. combine sugar and cornstarch. Stir in the reserved pineapple juice until blended. Add butter. Bring to a boil; cook and stir for 2 minutes or until thickened.
Pour over potatoes and pineapple. Top with cherries; sprinkle with cinnamon. Bake, uncovered, at 350° for 30-35 minutes or until heated through.