Research into Australian students' science, technology, engineering, and maths (STEM) engagement has highlighted that there are comparably fewer women enrolling in STEM programs and working in STEM industries. In Australia, males make up 84% of the total population with STEM qualifications, for example, a report in 2015 found only 13% of all engineers in Australia were women. Science, technology, engineering, art, and mathematics (STEAM), an approach to STEM education that encourages interdisciplinarity, creativity, innovation, and entrepreneurship, is a strategy that has the potential to increase girls' engagement with STEM. This research investigated the impact of the STEAMpunk Girls Program, funded by the Australian Government, on high school girls' learning and their teachers' teaching experiences. The program uses project-learning and design thinking strategies to enable the girls to gain confidence in themselves as change-makers with the capacity to generate solutions to real-world problems. Using a mixed method approach, the findings indicated that teachers and students were positive about the STEAMpunk Girls' experience, with significant increases in confidence and motivation in the girls at the end of the program.