De dos mundos

When election season starts, the race is on! But what do campaigns, candidates, polls, and the Electoral College have to do with voting for our nation's leaders? Using engaging, age-appropriate language and colorful photos, readers decipher the complex electoral process and learn how to get involved in the next election. Fully translated Spanish text.

This how-to kit contains instructions for making beadlings, itty-bitty creatures made out of shimmering glass beads strung on wire, and comes with materials for all nineteen projects. Mini criaturas irresistibles hechas a base de brillosas chaquiras y alambre de plata. Este libro contiene simples instrucciones e ideas para hacer estos trepadores, bichos voladores, gente y animales marinos y incluye toda la material para diecinueve proyectos.

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!

Planck consideró como tarea científica suprema la búsqueda de las leyes que rigen el absoluto, el invariante oculto en la realidad externa. Le cupo el privilegio de descubrir uno de esos elementos universales: el quantum de acción, la constante h.