10 cosas que puedes hacer para ahorrar electricidad

What causes sound? How does sound travel? Sound begins when matter vibrates. Without this vibration sound could not move and nothing would make any noise. Starting with tiny molecules, this book explains the main concepts of sound and furthers understanding through a series of easy-to-do experiments that will appeal to readers of all ages.

De una u otra forma, el agua se encuentra en casi todos los rincones del planeta. Además de constituir el hábitat de miles de especies y formar parte de nuestro organismo, su presencia en grandes antidades nos ayuda a transportarnos y nos brinda espectáculos tan formidables como aterradores. Así, cada gota es muestra innegable, como se lee en este libro, de que la vida florece donde hay agua.\"

Insectos is one book in the Spanish-language Gran Atlas de la Ciencia series that covers today's most popular science topics, from digital TV to microchips to touchscreens and beyond. Perennial subjects in earth science, life science, and physical science are all explored in detail. Amazing graphics--more than 1,000 per title--combined with concise summaries help students understand complex subjects. Correlated to the science curriculum in grades 5-9, each title also contains a glossary with full definitions for vocabulary.

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.