Nathan Hale

Who were the earliest Americans? When, how, and from where did they enter and spread across the continent? And what is their relationship to modern Native Americans? Anthropologists develop theories to answer these questions based on the evidence they discover. Their theories—and the discoveries that prove and disprove them—are highlighted in this fascinating volume, full of awe-inspiring facts and incredible breakthroughs. Readers will feel like anthropologists and archaeologists themselves as they read about bones and artifacts, and what they reveal about the ancient cultures that roamed...

It is the third Monday in January and school is closed. But do you know why? It's Martin Luther King Jr. Day. Turn the pages of this book to find out what dream Dr. King shared with the world, who Mohandas Gandhi was, how one brave woman helped Martin Luther King Jr. change history. Each book in the Holiday Histories series describes one of America's holidays or special days. Explore the history of each day and learn the real reason why it is important. Discover what special meaning each day might have for you.

¿Cómo son las cosas en el otro lado del mundo? ¿Somos tan diferentes a quienes allí viven? Aquí también nos propone darle una vuelta a esas ideas. La autora nos contó que este cuento nació mientras realizaba unas ilustraciones para El Salvador... ¡y se nota! Su colorido es una hermosa referencia gráfica a ese país de Centroamérica, tan parecido y tan diferente a la Argentina, el hogar de Paula. Alejo, el cuento del niño que juega haciendo mucho ruido, también es obra de esta talentosa autora integral.

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.