Historias para leer en la oscuridad

¿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 ...

Un práctico libro que engloba diferentes contenidos, con explicaciones muy sencillas e ilustraciones adaptadas, para tratar los temas preferidos de los más pequeños. Con esta enciclopedia podremos resolver las dudas más diversas con claridad y precisión.

If asked to define a forest, readers might say, "It has a lot of trees." But many places have a lot of trees. So, what makes a forest a forest? Readers discover that a forest is unlike any other biome on Earth. And a temperate forest is even more specific. Readers learn the many life cycles found within a forest and how the energy pyramid explains the numbers of forest plants and animals. In addition, readers learn by examining how forces usually considered destructive work to help forests survive. 32pp.

The 20th century saw many new inventions. Changes came fast and made life easier. Cars, planes, TVs, and cell phones were all invented in the 1900s. What other important things were invented during this time? From electricity to emoji, this Spanish nonfiction book will keep students engaged in reading as they build their literacy, vocabulary, and comprehension skills. Important text features include a glossary, index, and table of contents. The Reader's Guide and culminating activity require students to connect back to the text as they develop their higher-order thinking skills. Check It Out! ...