I discovered this book when I was in fourth grade or thereabouts, quite by accident in the public library. Because it seemed to be about animals (it is about storks, but it's about people even more), I took it home. And it became one of three or four books that I reread every year or two thereafter. I've read it at least three times since I finally bought my own copy as an adult.
Why is it so enchanting? I realized last night as I reread it yet again that The Wheel on the School says effectively in a story what most of today's children's books try to say in cliches and lectures: You are special, and people who are different from you are special too. Why is the message and the book effective? Because each person in the town realizes he or she, or the others in the town, is an important part of the town as the person actually contributes to it. No one is sitting around discussing self-esteem, but, for example, the town's fat boy, who usually gets left out of games, discovers he is strong, and the town's grumpy cripple becomes a leader, as they take part in what has become the town's mission--to bring storks to Shora. The old people emerge with stories and with memories of their own childhood longings and feats, and the adults and children work together. The book represents adults the way children see them (mysterious, sometimes scary, sometimes annoying, but protective, stronger, and wiser than the children), not with today's irreverence or irrelevance and not in a way where they take over the book or the children's project.
The book was a balm to me as a kid, the child who was left out of everything, and who discovered in real life, with Lina, that sometimes old ladies make good friends when children don't. And now as an adult with friends ranging from children to old ladies, I still find the book warm and almost magical.