Thomas Jefferson no firmó la Constitución (Thomas Jefferson Didn't Sign the Constitution)

Descubre a 25 supercient�ficas que cambiaron el mundo y demostraron que �las chicas son de ciencias! #ChicasDeCiencias �Sabes cu�ntos descubrimientos cient�ficos debemos a las mujeres? Aunque en los libros de historia parezca que las ciencias son cosa de hombres, de eso nada: desde Agnodice, la primera m�dica conocida de la historia, hasta Rosalind Franklin, la qu�mica que descubri� la estructura del ADN, pasando por Vera Rubin, la astr�noma que vio lo que nadie ve�a, las mujeres han sido pioneras en ciencias desde el inicio de los tiempos. Y aun as�, �podr�as...

Born in 1452, Leonardo da Vinci is still, today, considered one of the most talent people to have ever lived. From his world famous paintings and drawings, such as the Mona Lisa and the Vitruvian Man, to his ingenious inventions of the parachute, the helicopter, and the military tank, da Vince was always a step ahead of his time. Discover the origins of a man who refused to be defined by just one vocation. Whether science and engineering or architecture and art, Leonardo da Vinci was the ultimate Renaissance Man.

Veteran’s Day is a day set aside to thank the men and women who risk their lives protecting America. Each year on November 11, we celebrate what they have done for our country. Learn more about the history of this important holiday, such as why it is on November 11 and what Americans do to celebrate.

As a land that’s constantly in flux, Earth sometimes reveals clues about the plants, animals, and other organisms that lived long ago. Fossils teach us much about what life was like millions of years ago, answering the questions of how Earth changed and maybe even why it changed. This essential Earth science topic is thoroughly explained through manageable text, fact boxes, informational charts and diagrams, and a glossary and index. Readers will become young Earth detectives by the time they’re through with this text!