The purpose of the study was to conduct a preliminary efficacy evaluation of the Better Futures model, which is focused on improving the postsecondary preparation and participation of youth in foster care with mental health challenges. Sixty-seven youth were randomized to either a control group that received typical services or an intervention group, which involved participation in a Summer Institute, individual peer coaching, and mentoring workshops. Findings indicate significant gains for the intervention group on measures of postsecondary participation, postsecondary and transition preparation, hope, self-determination, and mental health empowerment, as compared to the control group. Youth in the intervention group also showed positive trends in the areas of mental health recovery, quality of life, and high school completion. Implications for future research and practice are discussed, while emphasizing the capacities of youth in foster care with mental health conditions to successfully prepare for and participate fully in high education.