This remount of Matt Larsen's charming 40-minute kiddie musical remains a labor of love filled with lots of learning--and laughs. The Paper Spaceship puts the issue of personal size into a cosmic perspective as the undersized Wendy (a plucky Molly Hale) gets help from two engaging aliens; residents of a flat world, they arrive as a very special delivery, having mailed themselves to the post office where Wendy's dad works. With help from a willing audience, Wendy protects her two-dimensional buddies from both neighborhood bullies and premature death by trash disposal. Larsen's staging keeps the silly stuff sufficiently serious to overcome even the largest attention deficit. Jeffrey L. Shivar's songs, bubbling over with clever lyrics, would fare better if the taped musical accompaniment could be turned down a few notches. Through 3/5: Sat 2 PM. ComedySportz, 2851 N. Halsted, 773-549-8080. $5-$10.