This paper reports the results of a randomized trial of the College Possible program, which provides two years of college preparatory work for high school juniors and seniors in Minneapolis and St. Paul. The trial involved 238 students, including 134 who were randomly selected for admission to the program. The results indicate that the College Possible program significantly increased both applications and enrollment to both four-year colleges and selective four-year colleges; we estimate that initial enrollment at four-year colleges increased by more than 15 percentage points for program participants, but find little evidence of any effect of the program on ACT performance or college enrollment overall. [For the What Works Clearinghouse Quick Review of this document, see ED544550.]