¿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.

Una col·lecció de llibres amb trencaclosques i un joguet mecànic. La granja, el mar, el jardí i la jungla són escenaris que amaguen una pila d'animals; els protagonistes d'aquests llibres estan encuriosits per descobrir-los. Per fer el camí tantes vegades com calgui.

Robbery, gunfights, murder--outlaws ran rampant all across the Wild West! Readers will be introduced to some of the most famous robbers and outlaws of the Wild West in this enthralling, Spanish-translated nonfiction title. With vivid images, informational text, and incredible facts and stories about such well-known figures as Billy the Kid, Butch Cassidy, and Jesse James, readers will be engaged from cover to cover!

En la mansión del conde Vázquez acaba de nacer un fantasma negro. La familia se lleva un tremendo disgusto porque un fantasma negro no se ve, y si no se ve, no asusta, y si no asusta, no le sirve de nada ser fantasma. ¿O sí? Cuando el resto de fantasmas está en apuros, el fantasma negro es el único que puede ayudarlos. "El fantasma negro" es una historia que nos habla de la diferencia con respeto, amor y mucho humor.

¡Estás a punto de descubrirlo! Abre este libro y explora el asombroso mundo de la biología: la ciencia que estudia a los seres vivos, desde las enormes ballenas azules hasta las microscópicas bacterias que viven en tu piel. En estas páginas conocerás de cerca plantas que comen carne, cerebros que te engañan, hongos cocineros y muchos otros seres extraordinarios. Sin perder el humor descubrirás que todo a tu alrededor... ¡está vivo!