Higher education has seen the accelerated development of blended learning (BL), active learning (AL), and STEM education. This study explores a proposed framework showing that BL affordances enable or constrain AL and that the relationship between BL affordances and AL influences student persistence in introductory science courses and the sciences. A multiple-case study examined an introductory physics course and an introductory chemistry course. Interviewed were two student volunteers from high-, average-, and low-performing groups from each course. Course documentations underwent content analysis, and in-class and online observations were evaluated using the practical observation rubric to assess active learning (PORTAAL). The researcher developed a survey instrument, blended learning for active learning (BL4AL), capturing students’ perspectives concerning AL through traditional and nontraditional learning methods for their persistence in the sciences. Findings indicated students from all levels had varying views of BL affordances. However, in-class clicker questions and a third-party tutoring service were discovered to consistently enable AL. Students’ perceptions of BL for AL had a medium effect on whether they would continue in the sciences.