Guía para los exámenes de Inglés

When we look up at the night sky you can see millions of stars, but what do you think we could see in space if we left Earth? If we could hop into a special ship and blast off, traveling billions of miles away from Earth, we’d see the Milky Way galaxy. In this book, readers take an incredible journey through that galaxy, exploring the universe and learning how it was formed and what will one day happen to these enormous groups of stars. From mysterious dark matter to the black holes at the center of galaxies, readers will also dive into the mysteries of the universe scientists have spent...

"While preparing for Christmas in Puerto Rico, seven-year-old Esmeralda asks the Three Magi for a baby doll like her cousin's, but when they bring something else instead she gains a deeper understanding of the meaning of the holiday."

People have been sending mail for a long time. But how they do it has changed a lot! Read about the history of mail as you learn to collect data. This Spanish math book combines math and reading skills and uses real-life examples of problem solving to teach subject-area content. The dynamic images, detailed sidebars, practice problems, and math diagrams make learning data measurement easy and fun. Text features include a table of contents, a glossary, an index, and captions to build vocabulary and increase understanding of math and reading concepts. An in-depth problem-solving section...

When President Thomas Jefferson bought the Louisiana Territory from cash-strapped France in 1803, he doubled the size of the United States without really knowing what he was getting. He dispatched Meriwether Lewis and William Clark and their Corps of Discovery to explore a territory that would include part or all of fifteen future states and to seek a water route to the West Coast. Westward expansion began immediately, all for the bargain price of 15 million dollars. This book richly explores this fascinating part of history.