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

This Title Teaches Students That Everything Is Made Of Matter, And That Physical Changes Create Different Forms Or States Of Matter. Gives Examples Of These Different States In Easy To Understand Text And Introduces Students To The Law Of Conservation Of Mass.

Using helpful maps, charts, and intriguing facts in conjunction with vibrant images and informational text, this fact-filled, Spanish-translated nonfiction title allows early elementary readers to explore the lush rainforests of the world. Readers will learn make their way from the forest floor to the understory, all the way to the canopy!

Se trata de una pregunta que nos inquieta solo de pensarla, tan profundamente dependen nuestras vidas y sociedades del mundo científico-tecnológico de la electricidad. Entre los grandes protagonistas de ese mundo, destaca un serbio que después de estudiar ingeniería en Graz (Austria), emigró en 1884 a América, instalándose en Nueva York; un serbio de imaginación y habilidades descomunales, un excéntrico sin miedo a lo desconocido, que gozaba montando espectáculos para promover sus inventos: Nikola Tesla (1856-1943). Es difícil apreciar cuánto debemos a sus inventos: sus ideas y...

With life-like illustrations and simple text, books in this series introduce children to different dinosaurs and the unique characteristics. Children learn the features of each dinosaur, what they ate, and whether they were predator or prey to other dinosaurs. The books also introduce fossils and how they play a role in our knowledge of dinosaurs' existence.