El ciclo del nitrógeno (The Nitrogen Cycle)

The use of calendars dates back thousands of years. Why are we driven to record time, and what would happen if we did not? Who created the concept of calendars? Why do different cultures use different calendar systems? And why are calendars so important to us? It is about "time" we found out! Created in collaboration with the Smithsonian Institution, this Spanish-translated Smithsonian Informational Text builds reading skills while engaging students' curiosity about STEAM topics through real-world examples. Packed with factoids and informative sidebars, it features a hands-on STEAM challenge...

In life there are lots of things that come and go, transform, or get left behind. It happens to everything . . . except this. This book deals with life changes and the passage of time with a great deal of sensitivity. To reinforce the message, each scene includes a page with special paper that invites us to witness the transformation.

History is full of unsolved crimes, mysterious disappearances, and strange sightings. Readers will discover some of the most well-known mysteries in history--including Amelia Earhart, Big Foot, and the Salem Witch Trials--in this fascinating, Spanish-translated nonfiction book. Featuring detailed images, intriguing facts, and informational text in conjunction with a glossary of terms and an index, readers will be enthralled from beginning to end! This 6-Pack includes six copies of this title and a lesson plan.

Mientras los misiles alemanes V-1 llueven sobre la campiña inglesa, el personal del hospital militar de Herons Park lucha por mantener la normalidad. La mañana siguiente a un ataque aéreo, el doctor Barnes se prepara para una intervención rutinaria: recomponer la pierna rota de un cartero. Pero antes de hacer siquiera la primera incisión, el paciente fallece a causa de la anestesia. Cuando el forense solicita una investigación, será el inspector Cockrill quien, abriéndose paso entre en una maraña de envidias y resentimientos, se enfrente a seis posibles culpables: tres médicos y...