I believe in using and defining "big words" for little people. However, each page of this book had phrases or long words that aren't in your typical 5-8 year old's vocabulary. These included truly wonderful words like "elongated paramecium" and phrases like "a woman ashore" (meaning that she was out of her desired place.) It is clear that author carefully chose words that have just the right sound to them and the book is lovely to read out loud. However, stopping to define these words and explain these phrases halted the progression of the story and breaks up the flow of the words.
My other criticism of this book is that it never really gets moving. The story line seems to believe that you already know who Rachel Carson is and are just looking for a few snapshots of points in her life. Each "chapter" stands alone and doesn't connect to the prior one or the next.
On the positive side, in addition to having wonderfully chosen words, the illustrations are beautiful. My children spontaneously commented on the illustrations.
While recommended for children ages 5-8 and being laid out like a typical picture book, this book isn't well written for children. If it is one that interests you, I suggest checking it out of the library before purchasing a copy.
One of the Wa State learning objectives for first grade is to learn about Rachel Carson. Her book "Silent Spring" is generally considered the mark of the begin of the environmental movement.