La historia de William Hoy

La Química es una ciencia experimental. Trata de desentrañar los secretos de la materia en cuanto a su composición, propiedades y transformación. A lo largo de la historia, este estudio ha ido evolucionando desde la simple observación exterior hasta las sorprendentes teorías actuales sobre su naturaleza íntima. La Química actual es una ciencia básica para otras ciencias, constituye el fundamento de infinidad de análisis que se hacen en diagnósticos médicos, en criminología, en paleontología, etc., pero también es una ciencia que participa en la vida cotidiana (desde el aire que ...

Learn how zookeepers at the National Zoo keep the animals healthy and happy. This Spanish book features a hands-on STEAM challenge and uses real-world examples to give insight into how the engineering design process is used to solve problems.

Animal trainers care for many different types of animals! Children will explore some of the methods that trainers use, such as affection bonding and classical and operant conditioning, while simultaneously gaining an understanding of animal instincts and animal rehabilitation. Readers are invited to learn about the variety of animals that trainers work with and are encouraged to find an area of study to focus on if they want to become an animal trainer. With stunning images, interesting facts, a glossary of useful terms, informational text, and an interview with a real-life animal trainer,...

These biographies introduce young readers to important figures in American history. Ideal for reports and correlated to the social studies curriculum, the series presents a straightforward account of each individual's life and times and describes how each person contributed to the shaping of our nation.