Silverman 
Utilizo máquinas simples [PDF ebook] 
I Use Simple Machines

A short guide to the mysteries of time, space, and the nature of existence as expressed in various media.The author records his own views on time and space mysteries with accompanying food, art, and …

Welcome to the wonderful and wacky world of Words, Werds, W-oh-er-dz! A fun and creative look at some of the funny, tricky, and interesting words we use every day. Words that sound the same but are s …

Why do children resemble their parents and siblings? Introducing young readers to the fascinating world of genetics, this educational resource presents the main concepts of the science, including wha …

A kind king in a far off land has been hiding his ears from everyone in his kingdom – even his wife, the queen! He has horse’s ears on his head and he is afraid everyone will laugh if they find out.. …