Agujeros negros (Black Holes)

Introduces the concepts of short and tall, comparing some of the world's shortest and tallest animals.

Este libro es una gran ayuda para que los niños quieran más y traten mejor a su Ángel de la Guarda, al Custodio que Dios nos ha puesto a cada uno para llevarnos al Cielo.

Did you know that the first wheel was not invented for transportation or that the system used to create computers was based on the functionality of a sewing machine? In a fun way, this book teaches the history behind inventions that have changed the way we live, from Ancient Mesopotamia to the present. Important details appear at the bottom of each page, including the name of the inventor, the time period, and the place where it occurred.

What is work? You may think work is doing chores or going to a job, but you do work every time you move something from one place to another. With experiments that demonstrate these fundamental concepts, discover how you work, and how simple machines make doing work easier.