This research examines the characteristics of reader understandings that vary from those stated in the text. Eighty-seven fourth graders orally read complex academic literary and scientific texts, followed by probed retellings. Retold ideas not directly supported by, or reflective of, the texts were identified. These differing understandings served as a foundation for the development of a taxonomy that classified them by type: conflation, conceptual knowledge, text/rhetorical structure, lexical knowledge, cause/effect, extension, association and misremembering. Approximately 60% of the differing understandings across the texts were conflations and extensions. However, particular texts did reflect particular types of differing understandings. In general, differing understandings were found to be reflective of the very active nature of the comprehension process. These meanings serve as a challenge to the current emphasis on close reading and the generation of text-based meanings because the natural consequence of such activity are differing understandings.