¿Por qué hibernan los animales? (Why Animals Hibernate)

When rocks change because of environmental conditions, the new rocks are called metamorphic rocks. A rock's chemical or physical makeup may change because of conditions such as temperature, stress, or pressure. Your readers will learn fascinating facts including where metamorphic rocks are most commonly found, the different types of metamorphism, and how metamorphic rocks are identified. Full-color photographs depict these rocks in nature. A helpful graphic organizer shows how these fascinating rocks form.

Diamonds and salt are both minerals, but diamonds are more rare than salt. Curious readers will learn what physical and chemical conditions must be present for minerals to form. They'll discover how minerals are identified and how they are used in daily life. Informative and interesting text presents readers with this science content in a fun way. A graphic organizer shows how different minerals are identified and fact boxes provide readers with exciting supplementary information.

Apartments, houses, log cabins, and houseboats are all kinds of homes, though they can look vastly different. Around the world, families settle into homes that can look quite different than these, yet serve the same purpose: to shelter. This volume will capture readers' imaginations, allowing them to view various types of homes, including the yaodongs of China and Queenslanders of Australia. Beautiful photographs serve to illustrate both architectural and cultural concepts.

California grew by leaps and bounds between the Gold Rush and 1900. People from different backgrounds emigrated to California from across America and around the world in search of a new life. This primary source reader focuses on immigration in California from the time of the Gold Rush to the end of the nineteenth century. Primary source documents allow students to see different points of view, and help students look at the world and current issues with a historical lens. This Interactiv-eBook builds literacy and social studies content knowledge through the use of intriguing primary sources...

"Ilustraciones divertidas para que los niños aprendan sus primeras palabras, en imprenta mayúscula"--Back cover.

Learn more about the renowned British scientist, professor, and author who spent his entire career trying to answer the question: "Where did the universe come from?" Stephen Hawking was born exactly three hundred years after the death of the scientist Galileo, so maybe it was written in the stars that he would become a famous scientist in his own right. Although he was diagnosed with a neurological disease at age 21, Stephen did not let the illness define his life. Known for his groundbreaking work in physics, and identified by his wheelchair and computerized voice system, Stephen continued...