Physics program for girls (PPG) is a two-week program held every summer since 2006, with the goal of engaging young women in inquiry-based physics experiments and to connect them with female science, technology, engineering, and mathematics professional role models. The program recruits young women to participate the summer after they have taken chemistry but before they enroll in their first high school physics course. Qualitative data collected over the years about PPG have shown that the program has been positively perceived by participants; 87% said they are more prepared for physics, 95% said that they think physics might be hard, but believe they can do it, and 91% said that they are positive that they will earn an A or B in their science course. However, there has not been any analysis of PPG students' performance in their introductory physics classes. The goal of this paper is to understand this impact using chemistry and physics end of semester assessment scores for girls who participated in PPG, as well as girls who did not participate in PPG but were from the same schools and had similar demographics to the PPG participants. Girls who participated in PPG performed comparably to girls who did not participate in PPG on chemistry, but PPG girls performed better than non-PPG girls in physics. This finding persisted even after controlling for the prior year's chemistry scores.