The Summoning Sphere by Jennifer Kloss
Approx. 30,110 words.
Published on April 25, 2011.
Ten-year old Blake and eight-year old Riley are just your average suburban brothers spending their summer vacation honing their skills at Mario Kart. But the boys’ predictable summer changes in an instant when they find a strange gold sphere in their neighbor's shed. Suddenly the boys are whisked away to a medieval world where they must help save a princess in danger.