Energía del viento

Defines screws, explains their functions, and suggests simple experiments to demonstrate how they work.

Defines levers, explains their functions, and suggests simple experiments to demonstrate how they work.

Follows the life and career of the French scientist who proved the existence of germs and their connection with diseases.

Diego de Torres (1694-1770) ha pasado a la historia como el creador de uno de los textos más importantes de la literatura española, Vida, ascendencia, nacimiento, crianza y aventuras de Don Diego de Torres Villarroel.

In today's chaotic world, opportunities abound for youth to disengage from community and worship. Once this happens, young people often don't come back. The National Federation for Catholic Youth Ministry wrote From Age to Age in 1997 as part of multiple-year response, to increase youth participation in worship. The document sparked national dialogue on how Roman Catholic parishes might best reach out to and involve youth in Catholic worship. From Age to Age revisits the liturgical principles of Vatican Council II and applies them in creative ways. The document provides strategies to help...

The Industrial Revolution brought important changes to America. People began migrating to cities for work, and immigrants began to arrive in American in larger numbers than ever before as they looked for new employment opportunities. Readers explore the impact of the Industrial Revolution on U.S. migration and immigration patterns. As readers learn about essential social studies curriculum topics, engaging historical images and detailed primary sources hold their interest. This transformative period in American history comes alive for readers with each turn of the page.

Si ha de estallar el sol y ha de llevarse este inestable mundo así engendrado, si han de volver los átomos al caos de mil años luz, mil soledades, si el hombre ha de perder su leve imagen, ¿no ha de quedarnos sólo ir conversando esta ocasión tenaz de haberse amado, de haberse en lo fugaz imaginado?