Efforts to attract and retain women in science are increasing, yet girls and women are persistently underrepresented in science education worldwide, limiting their preparation for, access to, and opportunities in science-related careers as adults. Based on qualitative research conducted in six secondary schools in Tanzania and informed by UNESCO's Ecological Framework for Female Participation in Science, this study explored structural limitations and sustainable alternatives to girls' participation in science education. The study identified a number of structural limitations, including the dominance of patriarchal ideologies about science, the lack of female science teachers, inadequate resources for science learning and heavy domestic workloads. Similarly, increasing the supply of teaching and learning resources, motivating female students to study science, and raising awareness among students, teachers, parents and community members of the importance of girls' participation in science education were identified as key sustainable alternatives. Overall, interventions to address cultural and social norms related to gender stereotypes and gender equality in policies, legislation, media and teachers' pedagogical practices are essential to promote girls' participation in science education.