King Arthur, looking for an heir, creates a math puzzle that Vertex is to solve with his friend Radius. After several deductive leaps, Vertex and Radius discover the sword Edgecalibur in a cone in the castle with a height three times its base. The math (involving Euler's Law) is too dense for this book's audience, but the charming story, enhanced by warm, textured acrylic and oil illustrations, will carry readers along.

Gr 3-5-Neuschwander retells "The Sword in the Stone" from a mathematical angle. Readers follow along with Sir Cumference and Lady Di of Ameter as their son Radius and his friend Vertex set out to find Edgecalibur. Filled with riddles and puns, the story is sure to delight students with some geometry background. Geehan's bright oil, acrylic, and pen-and-ink paintings include all the visual details that the text needs to help solve this geometrical mystery. If your students have enjoyed the first three books in the series, they will certainly want this one. Make sure to share these gems with your math teachers. The books can be used to support educational initiatives such as multiple intelligences, and students who are strong in verbal/linguistic areas will appreciate the integration of literature into their math lessons.-Christine E. Carr, Lester C. Noecker Elementary School, Roseland, NJ Copyright 2004 Reed Business Information.