Low motivation in science education is alarming. Motivation toward science, as predicted by well-being and scientific inquiry, was examined. Predictive research design, stratified random sampling, survey technique, and multiple regression analysis were applied. The data from 185 STEM students indicates that the criterion was significantly predicted, fully affirming the Self-Determination Theory. Future researchers may explore additional variables to account for the unexplained 24.1% variance. Educators may enhance student-centered, inquiry-based learning and promote students’ well-being and school connectedness.