El malquerido

People today refer to the Midwestern and prairie states as flyover country. During the Civil War, crossing those areas was the biggest obstacle in uniting the East and West Coasts of our divided nation. An act of Congress in 1862 authorized the Central Pacific and the Union Pacific railroad companies to build a railroad that would link the coasts. Seven years later, on May 10, 1869, an overwhelmingly immigrant labor force completed the task when a rail line was join in Promontory, Utah. The states had become united at last.

Learn about the many things humans can do to get warm when they are too cold. Created in collaboration with the Smithsonian Institution, this STEAM book will ignite a curiosity about STEAM topics through real-world examples. It features a hands-on STEAM challenge that is perfect for makerspaces and that guides students step-by-step through the engineering design process. Make STEAM career connections with career advice from actual Smithsonian employees working in STEAM fields. Perfect for English language learners, this Spanish book builds 1st grade students’ early literacy skills.

Para jóvenes lectores que además ejercen de espías, detectives, conspiradores y aventureros, este libro presenta todo tipo de sistemas, de lenguajes y de ingenios para crear y ocultar mensajes secretos. Desde las órdenes cifradas de Julio César, hasta el extraño mensaje en clave que escribió el hombre de la máscara de hierro, el código que utilizó Sherlock Holmes o la fabricación de tinta invisible, con ejercicios prácticos y un diploma acreditativo.

Focuses on NSTA Standards of understanding science and technology. Explores the position of motion of objects.