The Twin Princes by Tedd Arnold.
Tedd Arnold has long been one of my favorite authors for children. He captures the rumpus and joy of childhood in his spiraling art and child-friendly language. In this new book, he has created a medieval story where twin princes vie for the chance to be king. One brother, Fowler, is a real villain who cheats at everything. His brother, Henry, is the hero of the story: good to everyone, honest and caring. The story pits the two against each other in a race with a twist. Add to the twist the fact that it is a riddle for the children reading the book to solve and you have a winner of a book on your hands!
With puns galore, his usual accessible artwork, and mysteries and twists, this book will fly off the shelves. Add to it the medieval theme, and you have a book that can be used in many, many storytimes and units. Friendly and easy enough for kindergarteners, I could see sharing this with older elementary as well due to the great puns and the riddle.