Marta

Readers won't have to disassemble their favorite toys to discover what makes them work. This book explores electric, magnetic, and motion-powered toys from design to function. It introduces readers to the six simple machines and explains how they use force and motion to do work. Not every toy is a technological marvel. Readers learn about time-honored favorites including the rocking horse, Slinky, and rattles.

Correlated to the science curriculum, our Spanish-language series describes how the types of homes that different animals build reflect adaptations to their environments. Through simple, easy-to-follow text, each volume looks at each type of home as a shelter from predators and weather and a place to store food and raise young. Young readers also learn how animal homes and human homes fulfill similar needs and functions.

Learn the history of number systems with this engaging Spanish book! This text combines mathematics and literacy skills, and uses practical, real-world examples of problem solving to teach math and language arts content. Students will learn place value while reading about the number systems of the Egyptians and Romans, and also learn important vocabulary terms like cuneiform, binary systems, roman numerals, and more! The full-color images, math charts, and practice problems make learning math easy and fun. The table of contents, glossary, and index will further understanding of math and...

Deforestation, hunting and global warming have endangered countless species. The orangutan, okapi, giant panda and the blue whale are just some of the 30 species on the brink of extinction that are featured in this book. They need your help. The International Conservation Society illustrates how many of these species are left in the wild, and the latest status regarding their natural environment. You'll learn how you can aid endangered species and help sustain the ecosystems that give them life.