Círculos matemáticos

What causes sound? How does sound travel? Sound begins when matter vibrates. Without this vibration sound could not move and nothing would make any noise. Starting with tiny molecules, this book explains the main concepts of sound and furthers understanding through a series of easy-to-do experiments that will appeal to readers of all ages.

Un viaje interactivo para descubrir Sri Lanka, una isla en el Océano Índico, a través de su gente, vida salvaje, tradiciones, cultura, comida, historia, leyendas y deportes. El libro está completamente ilustrado a mano con objetos escondidos para buscar. Su páginas también tienen preguntas para que los lectores puedan relacionarse con lo leído. Pequeños y mayores lo podrán disfrutar juntos y explorar una tierra nueva a través de la belleza de la ilustraciones, animaciones y sonidos mágicos. ¡Vuela con tu imaginación! *Esta versión interactiva únicamente se puede leer con un...

If asked to define a forest, readers might say, "It has a lot of trees." But many places have a lot of trees. So, what makes a forest a forest? Readers discover that a forest is unlike any other biome on Earth. And a temperate forest is even more specific. Readers learn the many life cycles found within a forest and how the energy pyramid explains the numbers of forest plants and animals. In addition, readers learn by examining how forces usually considered destructive work to help forests survive. 32pp.

Introduce readers to the various ways they can participate in volunteerism with this Spanish-translated nonfiction title. Readers will discover many different charities and programs, including The Salvation Army, Feeding America, Habitat for Humanity, and Doctors Without Borders through vivid images, charts, and informational text. This nonfiction title aids in encouraging children to make a difference in their own communities by writing to newspapers or politicians or by participating in fund-raising and various programs or charities.