Por qué?

Rhyming text and photographs follow a pumpkin patch as it grows and changes, from seeds to plants to pumpkins ready to harvest, to jack-o-lanterns and then to seeds again. Simultaneous.

Louis Pasteur, Carlos Juan Finlay, Lynn Margulis, Margarita Salas, Jean-Jacques Muyembe, Francis Mojica, Katalin Karikó... Científicos y científicas que han cambiado nuestra vida son los protagonistas de este emocionante recorrido por la historia de la ciencia. Hoy todos conocemos la vacuna contra la covid-19, pero nadie se tomaba en serio a Katalin Karikó, la científica que la hizo posible, cuando empezó sus investigaciones. Igual que ella, los cazadores de microbios a lo largo de la historia se han enfrentado a menudo a la incomprensión y la indiferencia. Armados tan solo de...

Describes the impact of the Ford Model T automobile and the assembly line that built it on the automotive industry and American society, and recounts the life and career of their inventor, Henry Ford.

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.