The purpose of this study was to examine the relationship between the collective efficacy of teachers and student achievement at economically disadvantaged middle school campuses. The population of the study consisted of Texas campuses that served economically disadvantaged students and received a campus rating of Exemplary or Academically Unacceptable for two consecutive years, according to the Texas Education Agency (TEA). The data shows that significant differences exist between the collective efficacy of teachers from Exemplary and Academically Unacceptable campuses. It was also discovered that the Assessment of Teaching Competence (GC) and Analysis of Teaching Task (TA) is higher for teachers from Exemplary campuses versus that of teachers from Academically Unacceptable campuses. The quantitative findings presented in the study provide further knowledge on the relationship between collective efficacy and student achievement. This study has found that the collective efficacy of a campus can influence student achievement at the middle school level.