The underrepresentation of women in science, technology, engineering, art, and mathematics (STEAM)-related fields remains a concern for educators and the engineering community. Females tend to need more social support and learn better within a group. Using Project-based Learning (PjBL) seems to provide a supportive approach for female students to engage with STEAM. We adopted IDEO’s design process to evaluate the progress both female and male students made after participating in a PjBL-STEAM course. 137 high school students were recruited in this course to tackle the task to build a truss tower. Both female and male students evidenced significant progress in all constructs of engineering design thinking ability. In addition, there was no significant difference between female and male students’ posttest result. Our research echoes earlier research that female students can benefit from group work and develop substantial learning outcomes from PjBL-STEAM course.