Teachers are at high risk for stress, negative emotion, and job dissatisfaction, which has been linked with health problems and early attrition. Humor has been found to relieve various forms of stress. However, there is a gap in the literature regarding humor effects on teacher stress and its related consequences. The purpose of this quantitative, treatment-control group intervention study, based on Lazarus and Folkman's transactional theory and Kant's incongruity resolution theory, was to determine if humor influenced teacher stress, affect, and job satisfaction as measured by pretest and posttest Teacher Stress Inventory (TSI), Positive and Negative Affect Schedule (PANAS-X), and Teaching Satisfaction (TSS) surveys. The hypothesis was that humor would influence teachers' perceptions of stress, affect, and job satisfaction. For this study, 51 teachers from a central western school district were randomly divided into humor and control groups and completed the instruments. Treatment group participants then watched comedic videos and participated in humorous, small-group discussions during a stress workshop and completed follow-up surveys. Members of the control group completed posttest surveys before the videos and discussions. Results of analysis of covariance tests indicated that the humor intervention resulted in a statistically significant change in stress and positive affect compared with controls; however, there was no change in negative affect or job satisfaction. Results indicate that brief exposures to humor can have a significant impact on stress and positive affect. Implications for positive social change include decreased teacher stress-related illnesses and taxpayer costs and potentially improved quality of academic instruction. [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/en-US/products/dissertations/individuals.shtml.]