¡Respeta las reglas! (Respect the Rules!)

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!

La agenda escolar permanente de vampiros y terror te ayudará a organizar todos los datos, horarios, controles, etc. que quieras recordar durante el curso escolar, y al mismo tiempo te divertirás con sus escalofriantes historias y sus asombrosos dibujos. I

Mitad hada, mitad vampiro, ¡totalmente única! Un libro ideal para regalar en el que Isadora Moon y su prima Mirabella te cuentan todos los secretos de su magia. Ahora vas a poder descubrir todos los sus trucos de Isadora y su prima Mirabella para ser tan mágico como ellas. Encontrarás un montón de consejos, actividades, manualidades... ¡y ¡mucho más! El rosa y el negro, y ahora también el morado, vuelven a combinarse en este libro, consiguiendo... ¡el libro más mágico y brillante que ha existido jamás!

Learn more about the renowned British scientist, professor, and author who spent his entire career trying to answer the question: "Where did the universe come from?" Stephen Hawking was born exactly three hundred years after the death of the scientist Galileo, so maybe it was written in the stars that he would become a famous scientist in his own right. Although he was diagnosed with a neurological disease at age 21, Stephen did not let the illness define his life. Known for his groundbreaking work in physics, and identified by his wheelchair and computerized voice system, Stephen continued...