This research evaluated the impact on students' academic achievements of a pre-college outreach programme implemented by a Chilean higher education institution. This programme benefits students in their last year of secondary education so they can better adapt to post-secondary education. Specifically, we assessed whether freshmen enrolled in 2017 in the institution that implemented this initiative and who attended this programme during 2016 as secondary school students performed better than students at this same institution but who did not take part in this scheme. A quasi-experimental design was applied using the method propensity score matching. The results showed that students who participated in this outreach programme had better average grades and attendance levels than those who did not take part in this initiative. In addition, it was found that this programme does not have a significant impact on student retention rates.