I read this way back in grade school. Though I didn't know it at the time, 
Lionboy is a strange attempt at kids' magical realism. Main character Charlie Ashanti can speak to cats and somehow ends up running away from some evil no-name villains and stowing away on a circus boat. The idea is that he'll ostensibly find his missing parents or something to that effect. 
Lionboy is the first novel in a trilogy, so don't expect a whole lot of closure in this tome.
There's a fairly recent influx of YA novels about kids who save the world. It's pretty annoying, and 
Lionboy is no exception. There's really no moral, very little thematic content and an utter lack of character development; we're instead treated to Charlie's impossibly good luck as he sails around the world with a bunch of lions. If that sounds interesting, you might enjoy reading it to a child, but don't look for life-changing literary merit in 
Lionboy.