La historia de los sistemas numéricos: Valor posicional (The History of Number Systems: Place Value)

The Industrial Revolution was one of the most dramatic eras of all time, filled with fascinating people, strange events, and incredible stories. This period of great change comes into sharp focus through each spread with detailed, accessible language. Each fact is complemented with vivid, carefully-chosen historical images and illustrations, and a caption that adds just a touch more history. Readers are drawn deep into the facts not covered in history textbooks, like working conditions, inventions, failures, and characters, to make this important history lesson fun and engaging.

Más que un libro de viajes, el presente texto es un libro sobre los viajes, sobre cómo y por qué puede alguien llegar a hacerse etnólogo, y sobre el modo en que se integran las aventuras del explorador y las investigaciones del científico hasta llegar a formar la experiencia propia del etnólogo. El autor trata de analizar estas cuestiones cotejando sus recuerdos y proponiendo un recorrido que no renuncie a los pintorescos detalles, pero que a la vez los sitúe en una perspectiva más amplia.

Readers find out what it's like for astronauts to eat, sleep, and work on a manned space flight in this adventurous, Spanish-translated nonfiction title. Children will discover what it's like to be weightless in zero gravity, how Mission control helps keep astronauts safe, and what astronauts do during their free time through vivid photographs, interesting, informative text, and stimulating facts.

Humorous contemporary illustrations of traditional Mexican American proverbs, which appear in both English and Spanish.