We investigated pre-service elementary teachers' engagement in science and English language arts (ELA) instruction integrated in the context of a children's book. Teachers developed models and conducted a compare-and-contrast analysis after exposure to different accounts of the butterfly life cycle: a popular children's book, "The Very Hungry Caterpillar," and a scientific account from "National Geographic" called "Butterfly: A Life." The mixed-methods research was guided by the following question: What are the affordances and limitations of children's literature toward engendering an understanding of the butterfly life cycle for pre-service elementary teachers? Content analysis indicated that pre-service elementary teachers' abilities to compare and contrast the two accounts were not exceptional, as they failed to discriminate between ideas offered in the accounts and missed details of the key aspect of the butterfly life-cycle phenomenon: metamorphosis. However, the quality of participants' butterfly life-cycle models significantly increased after exposure to the scientific account. We suggest the potential for an additional ELA standard, asking and answering such questions as who, what, where, when, why, and how to demonstrate understanding of key details in a text, as a means for enhancing compare-and-contrast skills following these activities.