They waddled into stardom in National Geographic's March of the Penguins film. These guys are now nature's ROCK STARS! If you're age 5, you're probably as tall as an Emperor. But why do they throw up so much? March this way, and find out all! National Geographic supports K-12 educators with ELA Common Core Resources. Visit natgeoed.org/commoncore for more information.  From the Trade Paperback edition.