Laddertop, by Orson Scott Card and Emily Janice Card.  Illustrated by Honoel A. Ibardolaza.

#1 Laddertop series

#2 No others published.

Orson Scott card's world-building and Sci-Fi credentials need no introduction.  In this graphic novel, he teams up with Emily Janice Card and others to create a science fiction comic book which is fast-paced, atmospheric in tone, and illustrated in black and white.   A series of alien platforms lands on Earth, extending from the surface out to space, symbolic and actual ladders for humanity to climb out into the wider cosmos. Students Robbi and Azure are selected to be two of many recruits to attempt to understand and perhaps pilot these extraterrestrial enigmas. Can they unravel the true purpose behind Laddertop even though the adults who believe they administer it can not?  A worthy young adult space adventure novel for girls who love their manga well written and illustrated.

Citation: Card, Orson Scott, & Card, Emily Janice.  Laddertop. New York: Tor, 2011.