The power of a web-based forensic science game to teach content and motivate STEM careers was tested among secondary students. More than 700 secondary school students were exposed to one of the three web-based forensic cases for approximately 60 min. Gain scores from pre-test to a delayed post-test indicated significant gains in content knowledge. In addition, the game's usability ratings were a strong predictor of learning. A positive relationship between role-play experience and science career motivation was observed, which suggests a role for authentic virtual experiences in inspiring students to consider STEM careers.