It Is TimeBy: Lizzy Rockwell Series: I Like to Read Nonfiction for new readers! Egg to caterpillar to butterfly. A Level G science book for first graders to read on their own! Caterpillar hatches. She crawls. She eats. She poops. She grows. A caterpillar hatches, eats, becomes a pupa, weathers storms, and grows into a butterfly before flying away. An elegant, beautifully illustrated life cycle book that first graders can read on their own while learning basic