Retention of majors in science, technology, engineering, and mathematics (STEM) is a national problem that continues to be the focus of bridging and first-year experience programs. This article presents an innovative course, Scientific Thought and Methods, that targets students with low math placement scores. These students are not eligible for the introductory science courses in their major until late freshmen or early sophomore year. Course topics focus on development of scientific reasoning and the ability to engage effectively in all aspects of the scientific investigation process, including writing coherent lab reports that are based on experimental evidence. Significantly higher STEM retention rates were observed for students who completed the course compared with students of similar math placements who didn't enroll in the course. Assessment of student writing and reasoning skills, along with course evaluations, are provided. We believe that various attributes of the course, as discussed in the article, are essential for setting students up for success early on in their undergraduate programs. (Contains 2 figures and 3 tables.)