In this study, we use at scale randomized control trial among 18,000 secondary students in 181 schools in Tanzania (Zanzibar) to examine the effects of personal best goal-settings on students' academic performance. We also offer non-financial rewards to students to meet the goals they set. We find that goal-setting has a significant positive impact on student time use, study effort, and self-discipline. However, we do not find any significant impact of goalsetting on test scores. We find that, this could be partially because about 2/3rd of students do not set realistic goals. Third, we find weaker results on time use, study effort, and discipline when we combine goal-setting with non-financial rewards, suggesting that typing goal-setting to extrinsic incentives could weaken its impact. We also find that female students improved on outcomes much more than male students and that students coming from relatively weaker socio-economic backgrounds improved more than their counterparts.