We report a program for a summer science academy in chemistry, a section of the Chicago Academic Achievement Program (CAAP) at the University of Chicago, as a gateway to STEM for incoming first-generation students and other underrepresented student groups. Our program emphasized diversity in classrooms, students’ psychological safety and a sense of belonging to STEM, increased knowledge base, and overall college readiness. On the basis of feedback from participating students, the reported summer science academy in chemistry successfully prepared and motivated the CAAP scholars toward a STEM career direction.