<p>Scientific literacy and engagement in STEM fields remain significant challenges, particularly for students from low socioeconomic backgrounds. The research project <i>Arduínas: Girls and Women in Science</i> seeks to address this gap by providing hands-on opportunities for female post-primary students to develop STEM research projects using an open-source electronics platform and corresponding device, the Arduino microcontroller. This study examines how participation in such initiatives can foster the development of students’ science capital. Data were collected through semi-structured interviews, and a qualitative thematic analysis was conducted to identify key areas of Science Capital development. Findings indicate that early involvement in research projects enhances students’ science self-efficacy, strengthens their engagement with STEM disciplines, and positively influences their academic and career aspirations. However, structural barriers, such as inadequate infrastructure and socioeconomic disparities, continue to pose challenges, potentially limiting students’ sustained participation. By exploring the intersections of education, equity, and science engagement, this study contributes to discussions on expanding access to scientific knowledge and fostering inclusion in STEM education. The results highlight the importance of integrating Science Capital strategies into educational policies and early research programs to create more equitable and sustainable pathways into STEM careers.</p>