K-Gr 3–These are dual-purpose books, simultaneously written for emerging and more competent readers. Each chapter spread is divided into two sections that are written at two different reading levels. A simple question (“Where is this fish going?”) is posed to emerging readers, and the answer consists of easy sentences and basic explanations consistent with the abilities of students at that level. The question asked of fluent readers is more complicated (“What is spawning?”) and the answer is more in-depth. The table of contents identifies the animals that are covered (as opposed to the prompting questions) and will be of more use to better readers. “Words to Know” are divided by reading level; unlike the main texts, they do not duplicate each other. A brief list of books and Web sites is included at the back of each volume, although the reading level the materials support is not indicated. This is an interesting series that answers common questions children might have about animals and their lives, and the format makes it suitable for a wide audience.