This ninth-grade unit on language differences is intended to increase "the student's awareness or sensitivity to the ways in which language varies with the differing backgrounds and interests of those who use language," to develop his "abilities to adapt his language behavior to more effectively meet the demands of a variety of communication situations," and to increase his critical-thinking skills necessary for rational responses to emotive language. Excerpts from Jack London's "Martin Eden" and radio broadcasts of a farm market report, a professional football game, and a space flight are suggested to illustrate language differences based on age, sex, educational background, occupation, and avocation. Finally, in an attempt to show students that writers use language to reveal the backgrounds and interests of characters, the unit includes a reading list of novels in which this technique is evident. Teaching procedures, discussion questions, and introductory, transitional, and summary statements for lessons are found throughout the unit. (JS)