Hacia Los Confines del Universo

Five and counting! So far, astronomers have discovered five dwarf planets in our solar system. Pluto, which was once thought of as the ninth planet, is today classified as a dwarf planet. This book looks at the current dwarf planets, characteristics, size, and orbital patterns, as well as the three rules scientists follow to characterize these tiny, round space objects. Every day new discoveries are being made. Who knows how many dwarf planets we will find in the future! This book will allow students to understand that patterns in the natural world can be observed, used to describe phenomena, ...

Planet Earth gives us the things we need to survive. When it changes, it affects us all. But humans also affect Earth. It’s important that we take care of our planet so that it can continue to take care of us. This Spanish nonfiction book explores the subjects of human ecology and climate change in depth, and introduces students to important scientific concepts and vocabulary like desertification, deforestation, carbon dioxide, erosion, drought, fossil fuels, the greenhouse effect, and more. The colorful images, diagrams, sidebars, and text features will keep students connected to the text....

During the American Civil War, the United States was on the brink of falling apart irrevocably. As states seceded and brother turned against brother, hope for reconciliation was dim. This conflict, an essential topic of the social studies curriculum, is skillfully presented from its origins in the Southern slave-trade economy to bloody battles and, later, Reconstruction. Striking photographs and artwork of integral events and people will resonate with readers, while interesting sidebar information gives them more to reflect on about this terrible war and the lessons it taught us.

This complete Spanish translation of the highly acclaimed Isaac Asimov's 21st Century Library of the Universe is ideal for students still developing their English-language skills.