Linguists have long accepted the inevitability of linguistic variation as scientific fact. However, the general public continues to associate regional variation with low intelligence and to promote a non-regional, "accentless" English as the ideal. The result of this ideology, which ignores the natural diversity of all languages, is that speakers of marked, stigmatized dialects suffer from linguistic discrimination. As a solution to the problem of dialect discrimination, many linguists have attempted to disseminate knowledge about the natural diversity of all languages; however, only one study (Reaser, 2006) has quantitatively evaluated the effectiveness of such dialect awareness programs. The purpose of the present study is to determine if explicitly teaching dialect awareness can provide a successful counter to pervasive negative attitudes towards stigmatized dialects. In order to determine the effectiveness of teaching dialect awareness, I designed a dialect awareness unit for a first-year composition course. This unit incorporates previously published language and dialect awareness lessons with original lesson plans. This eight-week dialect awareness unit was taught to 19 students at Ball State University. The effectiveness of this dialect awareness unit was evaluated using a pre-test post-test study design; a control group was also given the pre-test and the post-test for comparison purposes. The results of the Likert-style scale pre-tests and post-tests were subjected to statistical analysis and the participants' written responses were analyzed qualitatively. The results of statistical tests and qualitative analysis of the students' answers support the hypothesis that the dialect awareness unit increased students' tolerance for stigmatized dialects and increased their linguistic awareness. The paired samples t-test for the experimental group was statistically significant, indicating that the dialect awareness unit made a measurable difference in their answers. The qualitative results reveal that although the participants learned basic linguistic facts about the nature of linguistic variation, a few participants resisted some learning objectives of the dialect awareness unit. These results indicate that college-age adults learned to be more tolerant of linguistic variation at approximately the same rate as Reaser's eighth-grade learners (2006). We can therefore conclude that college-age adults are not too old to unlearn myths related to the standard language ideology or to develop tolerance for nonstandard dialects. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]