Lo Que Necesitamos Y Lo Que Queremos

Introduces different kinds of light, the properties of light, and how light can create shadows of different shapes and sizes.

"Simple text and photos present the seasonal weather cycle and activities to do in each season"--Provided by publisher.

Dados los problemas medioambientales y económicos anejos al uso de combustibles fósiles, crece cada día el interés de formar a nuestros estudiantes en las energías renovables. Ahora bien, por experiencia sabemos que, cuando un alumno empieza a adentrarse en tales energías, se topa con ciertas dificultades sobre todo en el caso de la energía solar fotovoltaica. Ello se debe en ocasiones al desconocimiento de los fundamentos físicos de la célula solar fotovoltaica, o de las leyes que rigen la radiación solar, o de ciertas nociones básicas de electricidad... Esta obra trata justamente ...

This book introduces the reader to the nighttime world of the rat, including its habitat, activities, diet, and the unique things that it does.

Presents the life story of the Mexican-American labor leader who helped achieve justice for migrant farm workers by creating a union to protect their rights.

Celebrating tolerance and acceptance, each title in this constructive and accessible series focuses on the rewards and challenges of having a friend with a disability. Everyday situations are accompanied by informative sidebars that provide details about the highlighted disability.