High blood pressure can be caused by many factors, including stress, anxiety, diabetes, kidney disease, or obesity. In many people, there is no identifiable cause for their high blood pressure; this is known as essential hypertension (EH). Increasingly, children are being diagnosed with high blood pressure, which may lead to an increased risk of developing EH as adults. Therefore, the need exists for an effective blood pressure reduction program targeted toward youth. Research has shown that improving people's abilities to manage stress and anger reduces their risk of developing high blood pressure and heart disease. The Williams LifeSkills (WLS) workshop is a program that teaches people to cope with stressful situations. It has been shown to improve heart health, including blood pressure levels, in adults with cardiovascular disease. However, the effect of stress and anger management programs on blood pressure levels in youth has not been widely studied. Study researchers have developed and preliminarily tested a school-based anger and stress management WLS program. This study will evaluate the effectiveness of the school-based WLS program at reducing blood pressure and anger levels in high school students. If successful, this program could be implemented in schools across the country.