Assuming that aggressive behavior negatively affects all aspects of school performance (i.e. self-efficacy, affects, planning, motivation, and lack of outcome control) it would be logical to conclude that learning strategies to control affects can lead to improvements in school performance. To explore this hypothesis a group of 200 accessible students were given a questionnaire on aggressive behaviors and another on school performance, and then 30 of them with highest score on aggression and lowest on school performance were selected and randomly divided into two groups of experimental and control. Following the treatment of the experimental group with a course on affect control strategies, both groups were given the same set of questionnaires again. Data analyses show that the educational intervention has probably reduced aggression and improved some of the components of school performance (self-efficacy, planning, and motivation) while lowering scores on the other two components (p<0.001). Thus, the use of such effective interventions is recommended.