Designed (1) to create an interest in the study of language, (2) to help students understand something about the characteristics of language, and (3) to show students that language is a system, Unit I of the Oregon Elementary English Project offers the following six lessons: "Are Animals Like Humans? compares human and animal communication; "How Do I Recognize an Earthman?" demonstrates that all humans have a language which meets their needs; "What is a System?" examines the characteristics which some well-known systems have in common; "Is Language a System?" demonstrates how words go together in a system which makes it possible to predict some of the ways they will be used, and shows that students learn and use this system without realizing or thinking about it; "Why Do you Say It that Way?" demonstrates that the system of any language seems logical and natural to its speakers; and "Is Learning Forgetting?" explains how students learn the language and how they use it automatically without giving conscious thought to what they are doing. Each lesson is accompanied by suggested materials and procedures as well as possible extensions. (See CS 200 482-490 and CS 200 492-499 for related documents.) (HS)