The purpose of this study was to explore the impact a specific socio-scientific inquiry (SSI) unit has on student achievement and attitudes over the course of two years with two different implementations of the unit. Specifically, this study addressed the following research question: What impact does participation in an SSI unit have on student achievement and attitudes? A total of 212 students in 10 different biology classes participated in the study. Data collected included student pre- and post-test results from an assessment on genetics content, results from the state-delivered end of course assessment in biology, student focus group interviews, and results from a student attitudinal survey.