Education Northwest partnered with Oregon Mathematics, Engineering & Science Achievement (MESA) to measure the effect of program participation by comparing academic outcomes of two groups of students: those who participated in MESA and a matched group of peers who did not. All things that we could measure and are linked to student academic outcomes--prior achievement, federal program eligibility, and demographic characteristics--were the same or similar among individual MESA students and their matched peers. The only observable difference among data collected by the Oregon Department of Education is that one group participated in MESA, and the other did not. We found that MESA students were significantly more likely to graduate from high school than their peers. Specifically, students who participated in MESA were 3.13 times more likely to graduate from high school in four years than students who did not participate in the program. Stated another way, participating in MESA appears to increase the probability of graduating from high school in four years by 21 percentage points. We did not find any differences in how MESA interacts with graduation outcomes by students' gender, race/ethnicity, eligibility for the free or reduced-price lunch program, or English learner status. This means MESA is likely to boost the likelihood of high school graduation in four years for all students.