Exploremos las rocas sedimentarias (Exploring Sedimentary Rocks)

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.

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.

Invierno, primavera, verano y otoño--las estaciones son uno de los ciclos más familiares de la naturaleza. Pero, ¿por qué cambia el clima? Aprenda por qué los patrones climáticos cambian a lo largo de las estaciones. Winter, spring, summer, and fall--the seasons are one of nature's most familiar cycles. But why does the weather change? Learn why weather patterns change over the seasons.

Destined to become an etiquette bible for girls everywhere, this comprehensive and humorous reference provides a wealth of tips and tricks for how to act, feel, and look one’s best in every situation—whether at school, at home, with friends, or with romantic interests. This is an essential manual that proves that proper etiquette goes beyond just “please” and “thank you.” Destinada a convertirse en una biblia de etiqueta para niñas en todas partes, esta referencia comprensiva y humorística provee un buen número de consejos y trucos para cómo actuar, lucir y sentirse mejor en...

Por qué hay día y noche? Porque la Tierra gira sobre sí misma en 24 horas y porque el Sol no puede iluminar más que un lado a la vez.El cielo, las estrellas y la noche ilustrado por Christian Broutin, Henri Galeron y Pierre-Marie Valat, es un libro de la colección Altea Benjamín, la enciclopedia para responder a las preguntas de los niños que ya leen solos. ENGLISH DESCRIPTION Why is there day and night? Why does the Earth rotate on its axis and comes full circle in 24 hours? Why does the Sun only illuminate one side of the Earth at a time? Fascinating information about space and...

¿Y si el universo no pesara nada y la materia no existiera realmente? Lo que parecería ser una duda legítima para un erudito místico de los Vedas Indios es, en cambio, un resultado embarazoso de la aplicación de la Relatividad Restringida a las observaciones obtenidas por un grupo de astrofísicos, que han medido la radiación cósmica de fondo de nuestro universo. En los albores del nuevo milenio, el satélite WMAP, más allá de proporcionarnos una medida del cosmos, nunca antes obtenida, ha creado bastantes quebraderos de cabeza respecto al concepto de universo, en el que todavía hoy ...