Problem: Due to the current resurgence of attention given to high school students' taking courses in Science, Technology, Engineering, and Mathematics (STEM), research was needed to examine whether a relationship between the number of STEM courses a high school student, who graduates from high school and works in a non-STEM field, completes and the success of that student 10 years later. One measure of student success, future earnings, can be measured quantitatively and is included in the Education Longitudinal Survey of 2002 (ELS:2002) data set, an ideal source of information to evaluate this issue (Institute of Education Sciences, 2019b). Method: This quantitative study used a correlational design and a longitudinal survey, interview, and assessment research methodology to study the relationship between the number of STEM courses a high school student takes and his or her wages 10 years later with research-supported control variables. Multiple linear regression analysis was used to evaluate the relationships among these variables. Results: Based on a thorough data analysis, a relationship was found between wages and highest math course taken as well as highest science course taken. In contrast, while controlling for ability, the following variables did not show a significant relationship with wages: English as primary language, parents' highest education, parents' income, race, and sex, number of engineering courses taken, and number of technology courses taken. Conclusions: In advising high school students, if a student's only goal is to make more money 10 years following his or her sophomore year in high school, he or she may be advised to take more higher-level math courses for a slight increase in wages as there seems to be a relationship between highest math course taken and wages. This study is not designed to imply causation, however, so even this result may not establish the student's best interest. Further research would need to be conducted to account for what happens to wages after the initial eight years after graduation with more follow-up surveys beyond those completed to create the ELS:2002 database. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]