Los ciclos de vida de los peces (Fish Life Cycles)

Many insects hatch from eggs and molt several times as they grow bigger. Others, such as butterflies, undergo a complete metamorphosis. A common science curriculum topic, insect life cycles may be confusing because of these differences. However, this book breaks down these cycles into easy-to-understand steps in both accessible language and colorful diagrams readers can turn to for review again and again. The most important vocabulary needed to talk about insect life cycles is further explained in fact boxes and an extended glossary.

Venerado y vilipendiado a un tiempo, Lobachevski se cierne imponente sobre la matemática del siglo XIX. Al igual que sucede a la mayoría de los mitos, el Lobachevski real está oculto por capas de negligencia y desconocimiento. Su fantástica obra, argumentaban muchos, no era otra cosa que herejía matemática, una senda falsa. Lobachevski es una personalidad abrumadora, un soñador empedernido, un hacedor de mundos imposibles pero reales. Lobachevski es, para muchos, una persona desconocida. Este libro cuenta la historia de un hombre sencillo, pero sagaz, obstinado y profundo desde el...

Ants are so important to our ecology that some scientist fell that if ants ever disappear so might humans! SOY UNA SEMILLA es un libro de la serie Hola, lector! que muestra la diferencia entre dos semillas, asi como su evolucion hasta llegar a convertirse en plantas. Los ninos disfrutaran del texto dinamico con el que esta escrito este libro.

The need for speed is the motivating factor in this engaging, Spanish book. Readers learn the history of travel from the very slow to the supersonic and beyond, including everything in between. They learn and discover the factors that influence motion for all types of vehicles: land, air, and water alike. They also learn different ways to measure speed and read about energy uses for different vehicles. With greater speed comes greater risk. Readers learn how engineers are always seeking new and better ways to keep people safe as they travel faster and go farther. This 6-Pack includes six...

What is work? You may think work is doing chores or going to a job, but you do work every time you move something from one place to another. With experiments that demonstrate these fundamental concepts, discover how you work, and how simple machines make doing work easier.