Project EX is an eight-session teen school-based clinic tobacco use cessation program that involves the inclusion of enjoyable, motivating activities ("games," "talk show," and alternative medicine-type) to try to enhance quit rates among youth. This clinic program was tested in a three-group experimental design: clinic-only, clinic plus a school-as-community (SAC) component, and standard care control. Eighteen schools were assigned to the three conditions using a randomized block design. A total of 335 smokers participated in the study, making this the largest controlled teen smoking cessation field trial conducted to date. Seventeen percent of the smokers enrolled in the clinics had reports of having quit smoking for at least the last 30 days at 3-month follow-up (5 months after the program quit day), compared to only 8% of the control condition smokers over than same time period. The Project EX clinic component appears to be an effective means of tobacco use cessation among teens.