La vida amorosa de los animales

Mars is perhaps the most thrilling planet these days. With rovers exploring its surface and manned missions in the works, people are wondering if Mars is our next home! In this highinterest book, readers will learn more about Earth's neighbor, including what its climate and surface are like, why it's called the Red Planet, and about the recent discovery of water on its surface. They'll learn all this while solving "Your Mission" math problems that complement and support the text. This motivating volume is an engaging way to explore key aspects of science and math curricula.

Hay momentos en los que nos vemos abocados a tomar una decisión. Momentos en los que elegimos, de entre todas las opciones que la vida nos ofrece, un camino y no otro. Estas decisiones, que nos ocupan a menudo tan sólo unos segundos, determinan en realidad el resto de nuestra vida. Pueden cambiarlo todo en un abrir y cerrar de ojos. Esta novela es el relato de uno de esos momentos: de Berlín en 1984, de un momento que lo cambió todo y de las consecuencias y las huellas que dejó para siempre en los corazones de dos amantes. Hasta que no te descubras de madrugada pasando una página tras...

What's hidden in the woods? Look closely through three colored transparent sheets to discover hidden secrets. Start with green and nothing moves. As if by magic each sheet shows animals and plants coming to life. Watch nature's surprises emerge in front of your eyes.

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.