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

Although Earth is mostly made up of igneous and metamorphic rock, sedimentary rock covers about 75 percent of Earth's land surface. This means it's the most visible kind of rock on Earth. Sedimentary rocks form when sediment accumulates and compacts. Your readers will learn how sedimentary rocks form, the different types of sedimentary rocks, and how people use sedimentary rocks. Fun fact boxes provide readers with additional information. A helpful diagram illustrates how sedimentary rocks form.

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.

The rock cycle has been taking place for millions of years. However, geologists have only known about this phenomenon for about 300 years. Young terrestrial explorers are introduced to different types of rocks, where in the cycle these rocks fit, and where in Earth's layers each step takes place. Fact boxes provide readers with fun additional information. A diagram helps readers make sense of the new information they're learning.

Based on the #1 New York Times Best-Selling series, this timeline of world history gives a fresh take on global events, from King Tut to Malala Yousafzai. Basada en la serie más vendida del New York Times, esta cronología de la historia mundial ofrece una nueva visión de los acontecimientos mundiales, desde el rey Tutankamón hasta Malala Yousafzai. For the first time ever, the Who Was? subjects are gathered into a single title! The Who Was? History of the World is a journey along the timeline of history, noting the birthdays of 150 people in the series and what was happening in the world...

Bill Myers ha dedicado anos a la investigacion de fenomenos sobrenaturales e incluso ha hecho peliculas sobre el tema. En este libro comunicara su investigacion junto con entrevistas y experiencias de la vida real de siquicos, satanistas, personas que han sido poseidas e incluso raptadas por extraterrestres. Las historias que cuenta pueden dar la impresion de ser peliculas de Hollywood, pero se basan en acontecimientos reales."

Teach students about the years of change and reform between World War I and World War II. With this Spanish-translated book, readers will learn about events such as the Harlem Renaissance, suffrage, the stock market crash on "Black Tuesday," and the Great Depression. Primary source documents and images, and other engaging features, aid students in understanding the social studies content.

Young children are natural problem-solvers and always looking for answers, especially when it involves interesting animals. This Spanish-language edition of Scaly Swimmers provides young curious readers with striking visual clues and simply written hints. Using the photos and text, readers rely on visual literacy skills, reading, and reasoning as they solve the animal mystery. Clearly written facts give readers a deeper understanding of how the animal lives. Additional text features, including a glossary and an index, help students locate information and learn new words.