I'm feeling ambivalent about this story. It was good storytelling, easy to read, and especially good for kids who feel like they don't fit in. The narrator had some funny comments, but they were included so randomly and rarely that they were more like an interruption. And I didn't have a good sense of time and place before the falling in. 
 I generally feel like people who end up in other worlds, whether in books or movies, don't seem sufficiently freaked out to me.