Energía del viento

Defines levers, explains their functions, and suggests simple experiments to demonstrate how they work.

Follows the life and career of the French scientist who proved the existence of germs and their connection with diseases.

Defines screws, explains their functions, and suggests simple experiments to demonstrate how they work.

Got a fan of snakes, lizards, and turtles? Dig into this beginner's guide to reptiles from Cathryn and John Sill, creators of the award-winning About... series. Author and educator Cathryn Sill explains in simple language the basic characteristics that all reptiles share, while offering a look at many of the animals that fall into this diverse category, including ever-popular lizards, snakes, and turtles. The beautifully detailed paintings of noted wildlife illustrator John Sill depict reptiles in their habitats and highlight their unique aspects. An afterword provides more detail on each...

This Spanish-language series presents the complete range of math concepts and skills students are expected to master during the first grade. The series moves sequentially, from easiest to hardest concepts, with each book covering a different math topic. The first volume reviews the math concepts students learned in kindergarten. The next six books cover counting, adding and subtracting, tables and graphs, money, patterns, and measuring. The eighth volume is a summary of the math concepts students have studied throughout the year. Each book presents situations that show the relevance of math...

For soccer fans, the unstoppable Cristiano Ronaldo has become a household name. What goes into the making of such a phenomenal player? What was he like when he was young and still learning? This book takes a close look at one of the greatest soccer players in the world right now. Young readers will love to learn about his jaw-dropping achievements and also learn about what shaped him into a record-breaking athlete. Ronaldo's story will inspire both the curious new soccer fans as well as those already bit by soccer mania.

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...