Katherine McLean Brevard

When the Chinese invented gunpowder in 850, their explosive invention became the basis for almost every weapon used in war. It radically changed warfare all over the world, affecting the way battles were fought throughout the Middle Ages. When guns were invented five centuries later, the world was again transformed. Explosive weaponry was available to the individual, creating a new class of soldier and giving birth to the modern army.

Axel and his uncle find a note that describes a path to Earth's center! The men climb deep inside a volcano and discover amazing wonders. They also run into danger, which could trap them below the surface forever. These reader-favorite tiles are now updated for enhanced Common Core State Standards support, including discussion and writing prompts developed by a Common Core expert, an expanded introduction, bolded glossary words and dynamic new covers....