Adolescents are in a high-risk period developmentally, in terms of susceptibility to stress. A mindfulness intervention represents a potentially useful strategy for developing cognitive and emotion regulation skills associated with successful stress coping. Mindfulness strategies have been used successfully for emotional coping in adults, but are not as well studied in youth. This article details a novel proposal for the design of an 8-week randomized study to evaluate a high school-based mindfulness curriculum delivered as part of a two semester health class. A wellness education intervention is proposed as an active control, along with a waitlist control condition. All students enrolled in a sophomore (10th grade) health class at a private suburban high school will be invited to participate (n = 300). Pre-test assessments will be obtained by youth report, parent ratings, and on-site behavioral testing. The assessments will evaluate baseline stress, mood, emotional coping, controlled attention, and working memory. Participants, divided into 13 classrooms, will be randomized into one of three conditions, by classroom: A mindfulness intervention, an active control (wellness education), and a passive control (waitlist). Waitlisted participants will receive one of the interventions in the following term. Intervention groups will meet weekly for 8 weeks during regularly scheduled health classes. Immediate post-tests will be conducted, followed by a 60-day post-test. It is hypothesized that the mindfulness intervention will outperform the other conditions with regard to the adolescents' mood, attention and response to stress.