Exploremos las rocas sedimentarias (Exploring Sedimentary Rocks)

When winter hits, many people in colder climates spend most of their time indoors. But what do wild animals do? Some animals spend winters hibernating. Beginning readers will learn what hibernation is, why some animals hibernate and others don't, and how hibernating animals prepare for their long sleep. Full-color photographs grab readers' attention and allow them to draw connections to the narrative. Readers will love learning about this mysterious, restful time in some animals' lives.

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.

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.

Este libro nos descubre otra historia de los Kennedy, muy distinta a la desenfadada y frívola que se suele contar. La historia de dos hombres, el presidente y su hermano Robert, que mantuvieron una dura lucha contra las fuerzas oscuras de su entorno: contra los generales y los dirigentes del aparato de inteligencia, empeñados en arrastrar al país a una nueva guerra mundial. Una lucha que acabó con el asesinato de John en Dallas, que Robert estaba convencido que era obra de una conspiración del crimen organizado, la CIA y los grupos que planeaban una acción violenta contra Cuba, lo que...

"Dino" Don Lessem brings readers face-to-face with various dinosaur species, detailing their habitats, way of life and how they became extinct. An acclaimed dinosaur expert, Don Lessem has written more than 30 children's books, writes a popular dinosaur column in Highlights magazine, and was an adviser for the film Jurassic Park. Take a trip through dinosaur time to meet these deadly dinosaurs face-to-face: The Variraptor had pointy teeth with grooves like steak knives to saw through meat! The Draeomaeosaurus was the first raptor ever discovered. It had a very large brain! The Microraptor was ...

Si usted es de los que piensan que apenas hay relación entre la condición humana y las matemáticas, tiene que leer este libro. En él se encontrará con la mitología, la música, la guerra, la astronomía, la literatura... y las matemáticas viajando juntas a través del tiempo y del espacio; desde Egipto, Mesopotamia, la Grecia clásica o la Constantinopla asediada por los turcos hasta la Polonia ocupada por los nazis, Los Álamos de las primeras bombas atómicas o Hiroshima y Nagasaki. Un periplo fascinante desde el centro de la Tierra a los planetas exteriores del sistema solar, del...

This collection of some of the best-loved Bible stories will give young children an introduction to the Catholic faith.