¿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.

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.

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.

Explains the basic science of flight, the problems of getting vehicles into the air, different types of engines, and aircraft design, and includes instructions for making aircraft models.

Winning the American Revolution was just the first step. After defeating Great Britain, the American colonies were united in name only. How would this independent nation be governed? During the summer of 1787, representatives went to Philadelphia to solve the problem. The result, the U.S. Constitution, created a new government, establishing the foundations of a free nation and setting a new course for history.

Un libro para profundizar en el mundo de los escorpiones, la robótica y descubrir la relación entre ellos. Además, todo lo necesario para construir tu propio escorpión robot. ¡Cuidado! pica y le brillan los ojos.

From the candiru to the lionfish, there are so many kinds of fish on Earth. While all have different methods of production, the basic life cycle is the same, from egg to spawning swimmers. Readers are introduced to this general cycle as well as the important vocabulary needed to talk about it, such as “fry” and “spawning.” Accessible language and simple diagrams throughout the book provide a way for struggling readers to tackle science curriculum content.