I've been reviewing books for over ten years now, ever since I met Marilyn Courtot at a school book fair in Maryland. I was signing my then brand-new book (the one this blog's named for) and she was starting a newsletter about children's books, Children's Literature. Ever since then, Marilyn's been sending me a box of books every few months, and I have been reading and learning. Children's Literature has morphed into the CLCD, an online database subscribed to by libraries and institutions around the world.
If you're trying to write children's books, it helps to read lots of them. Newbery winner Linda Sue Park suggests it might be the single most important thing to do. The more you read, the more you begin to develop opinions of your own, learn to separate what you like from what you don't like. More, you learn to defend your opinions and cultivate your critical skills. All of which will stand you in good stead as you grow your own writing.