Dear Mr. Henshaw is a touching story, kind of a "coming-of-age" tale for an elementary school child. But instead of seeing this tale through a typical narrative, we see this character's growth through letters that he writes to his favorite author, Mr. Henshaw.
Cleary does a wonderful job demonstrating that growth, through decisions he makes and, most impressively, small, barely perceptible improvements in his writing.
I was quite surprised when Leigh expressed anger first at Mr. Henshaw for being late in answering the ten questions he sent him, and second for Mr. Henshaw asking Leigh to answer ten questions about himself. Leigh went from "Your friend", "Your Best Reader", to "Your Disgusted Reader".
One of the things that Mr. Henshaw suggested was that Leigh keep a journal. Leigh did so, and that's where we see the most tremendous growth of his character, as he talks about his feelings about his mom, his dad, and himself.
It's a wonderful book for kids, but also a terrific read for adults. Beverly Cleary never disappoints.