El ferrocarril transcontinental (The Transcontinental Railroad)

People today refer to the Midwestern and prairie states as flyover country. During the Civil War, crossing those areas was the biggest obstacle in uniting the East and West Coasts of our divided nation. An act of Congress in 1862 authorized the Central Pacific and the Union Pacific railroad companies to build a railroad that would link the coasts. Seven years later, on May 10, 1869, an overwhelmingly immigrant labor force completed the task when a rail line was join in Promontory, Utah. The states had become united at last.

Readers may never expect that they might free fall to Earth, but if they have ever dived into a pool, that's exactly what they've done. This book shows readers how Newton's three laws of motion affect divers, skydivers, and mountain climbers' movements. Readers discover who uses gravity, and who works against it, and all other forces that contribute to a successful dive or climb. After reading this book, readers can decide if they will ever be interested in engaging in one of these extreme sports.

The asteroid belt between Mars and Jupiter is an intriguing area of our solar system. Scientists have counted over 670,000 known asteroids there, but there could be millions more not yet found. Readers will discover much more about the asteroid belt in this highinterest book, which blends science and math. They'll read about several topics, such as space missions to the asteroid belt and the difference between an asteroid and a planet, and solve associated math problems-just like actual space scientists do!

En los primeros siete números de la colección te hemos enseñado a diseñar personajes, a escribir historias y desarrollarlas... Ahora es el momento de crearles un mundo y un ambiente real donde ambientarlas.

«En la soledad, el abismo» recopila en versos todo lo que no puede recopilarse en abrazos, esa ausencia indescriptible y el doloroso miedo de la fragilidad humana. Cada poema rasga el verso para encontrar la belleza en la soledad cotidiana y en la amargura de una soledad que sobrepasa lo inalcanzable. Cada soledad es un universo. Espero que puedas encontrar la tuya en el mío y, así, juntas, nuestras soledades bailarán su vals acompasadas.