Piedra de toque

You've only got one day to spend at the carnival-how do you make the most of your time? Students will learn how to measure time while reading about a fun-filled day at a carnival! This fiction Spanish book uses real-world examples to teach math concepts, and incorporates nonfiction reading to increase vocabulary and comprehension skills. The challenging practice problems, graphs, and sidebars provide many opportunities for students to practice their developing math skills, and apply what they've learned to their daily lives. Essential text features like a glossary, index, and table of...

Los espejos de Anclara es el poemario ganador del Premio Hispanoamericano de Poesia para Ninos 2008. Relata, desde la perspectiva de la infancia, la fantasia de una nina que se mira al espejo e imagina que sus ojos son dos puertas a traves de las cuales puede entrar para descubrir lo que esta encerrado en su interior: suenos, miedos, dolores, alegrias y anhelos. Es un libro que se desarrolla en el limite entre la realidad y la fantasia y los conductos por los cuales estas dos se comunican.

Many animals live in water, but only some can be defined as fish. Twenty-eight thousand species of fish exist, each with different characteristics. Readers from grades one through four will learn that fish have a distinct impact on their ecosystem and will see how fish survive when well-adapted to an uncompromised environment. Beautiful photographs demonstrate the great diversity of fish and accompany intellectually stimulating explanations of their varying roles and traits. From page to page, what a fish is unfolds in vocabulary call-outs, insightful questions, and relatable...

Planck consideró como tarea científica suprema la búsqueda de las leyes que rigen el absoluto, el invariante oculto en la realidad externa. Le cupo el privilegio de descubrir uno de esos elementos universales: el quantum de acción, la constante h.