O Grande livro da água

There is a contest at a school to design a new playground. The students use blocks to build their models. As they build, they use three-dimensional shapes. Some students build a train out of blocks for the younger students to play on. Can you guess which three-dimensional shape they use for the train's wheels? Read to find out which design wins.

Imagine traveling at half the speed of a jet plane without ever leaving the ground! Students will discover the technology that makes such speeds possible, from special tracks and safety precautions to aerodynamically designed trains. What are the limits to the speed of trains? What imposes those limits? Students also will read about the future of passenger train travel, from flying trains to trains that use huge magnets to levitate inches or centimeters off the track. Some trains safely reach speeds of more than 200 mph!

Esta leyenda mexicana nos relata la hermosa cermonia de los voladores, ceremonia que aún tiene lugar en Papantla y otros pueblos del destado mexicano de Veracruz.

Ambrose Gwinnett Bierce (1842-1914?) dedicó buena parte de su carrera literaria al periodismo satírico, así como a escribir relatos de terror que le aseguraron un lugar destacado en la historia de la literatura norteamericana como un consumado maestro del humor negro. Su participación como romántico voluntario en la Guerra Civil Americana, en cuyos horrores y sangre chapoteó hasta caer malherido en la batalla de Kennesaw Mountain, le inspiró una serie de relatos que recopiló años más tarde en uno de sus libros más conocidos, Cuentos de soldados y civiles (1891). Esta experiencia...