This study is a multi-component Positive Psychology Intervention (PPI) with the goal of improving daily happiness and classroom behavior in a sample at-risk high-school students. PPIs have increasingly been used in school settings to enhance student well-being, student success, and to increase positive affect. The current study utilized a multiple baseline design, across five adolescents, to examine whether a manualized PPI implemented in individual school-based counseling sessions with at-risk high-school students, would lead to increased happiness, improved classroom behavior, and life satisfaction, measured through a Daily Happiness survey, the Direct Behavior Rating (DBR), General Happiness Scale, Brief Multidimensional Students' Life Satisfaction Scale, and the Student Life Satisfaction Scale. Results demonstrated high variability in the data and an overall null effect of the intervention on the two dependent variables of daily happiness and classroom behavior. Limitations included individual impacts of outside factors on student reports and behavior. Due to the small scale of the study and lack of observed intervention effects, more research is needed to draw conclusions about the application of the intervention. However, social validity data revealed that school-based mental health professionals may still consider this intervention to teach students strategies to improve life satisfaction.