Halloween

Imagine traveling at half the speed of a jet plane without ever leaving the ground! Students will discover the technology that makes such speeds possible, from special tracks and safety precautions to aerodynamically designed trains. What are the limits to the speed of trains? What imposes those limits? Students also will read about the future of passenger train travel, from flying trains to trains that use huge magnets to levitate inches or centimeters off the track. Some trains safely reach speeds of more than 200 mph!

Una colección de libros que combinan historia del arte con imágenes, espectaculares pop-ups y divertidas actividades para descubrir las obras y los artistas más reconocidos de todos los tiempos. Tras la Mona Lisa y Alexander Calder, ahora ponemos al alcance de los más pequeños la obra de un artista que revolucionó el mundo del arte: ¡el genial Andy Warhol!

Defender la Luz Mientras el mundo occidental caía en la oscuridad, ella se atrevió a defender la luz. Hipatia de Alejandría, nacida en el año 355, tras el reinado de Constantino, vivió en un Imperio Romano que se derrumbaba, un mundo en el que la obediencia a las autoridades religiosas triunfaba sobre la ciencia, en el que la razón y la lógica amenazaban el nuevo orden mundial. Era un mundo al borde de la Edad Media, un mundo que decidía la cuestión de la ciencia versus la religión, la libertad versus la ortodoxia, la tolerancia versus el odio. Durante más de 40 años, Hipatia se...

Who were the earliest Americans? When, how, and from where did they enter and spread across the continent? And what is their relationship to modern Native Americans? Anthropologists develop theories to answer these questions based on the evidence they discover. Their theories—and the discoveries that prove and disprove them—are highlighted in this fascinating volume, full of awe-inspiring facts and incredible breakthroughs. Readers will feel like anthropologists and archaeologists themselves as they read about bones and artifacts, and what they reveal about the ancient cultures that roamed...