La historia de los sistemas numéricos: Valor posicional (The History of Number Systems: Place Value)

¿Qué significa jugar limpio? Cumplir las reglas, ayudar a los demás y respetar los turnos son algunos ejemplos. Este libro se combina con el título de ficción Tu turno. What does it mean to play fair? Following rules, helping others, and taking turns are a few ways to do it. This Spanish book pairs with the fiction title Tu turno.

Mars is perhaps the most thrilling planet these days. With rovers exploring its surface and manned missions in the works, people are wondering if Mars is our next home! In this highinterest book, readers will learn more about Earth's neighbor, including what its climate and surface are like, why it's called the Red Planet, and about the recent discovery of water on its surface. They'll learn all this while solving "Your Mission" math problems that complement and support the text. This motivating volume is an engaging way to explore key aspects of science and math curricula.

Ismael trabaja como pescador a lo largo de las costas del norte de África, a pocos kilómetros de la anhelada Italia. El mar es parte integral de su vida, fuente de sustento y símbolo de pertenencia a un grupo. Pero cuando el mar, de repente, le arrebata a su padre, a Ismael no le queda más remedio que abandonar todo lo que conoce y ama, y emprender un viaje desesperado en busca de fortuna y de un lugar al que realmente pueda llamar hogar. Esta novela muestra la cara más amarga de la inmigración, aquellas noticias que cada día destacan en los informativos sobre las miles de personas que ...

Our closest solar system is about 10 light years away. It has two main types of planets. Some are rocky and small, like planet Earth, while others are huge balls of gas, like Jupiter. Learn about how astronomers once thought our solar system was the one and only, to how they have now discovered hundreds of stars with planets orbiting them, which means there could be billions of solar systems in outer space! Just maybe, these alien worlds could host life, like our own amazing planet. This book allows students to use observations of the Sun, moon, and stars to describe patterns that can be...