Despite the profound concerns around gender disparity, and the best efforts of organisations to address the lack of diversity in the computing profession, women remain significantly underrepresented. This situation is mirrored in secondary schools, with many single sex girls’ schools in particular, not offering computing as a subject in the final year of schooling. The RoboCats program was established as part of a highly specialised robotics program run as an out-of-school co-curricular activity targeting secondary school girls from Years 9 to 12 (aged 15–18) to design, build and program a sophisticated game-playing robot through the use of industry-level hardware and software. Industry mentors, who were computer scientists and mechatronic engineers, supported the students in developing their Java programming knowledge and skills. Drawing upon qualitative data taken from 2014 to 2020, the authors share their approach, the benefits and opportunities afforded to girls in developing their coding skills, via authentic real-world challenges.