It is hard to attract young persons to engineering and other science, technology, engineering, and mathematics (STEM) fields of education in Sweden. Factors, such as interest and ability, are affecting the educational orientation of students, and many studies suggest that there are gender related differences in students’ perceptions regarding different subject areas. Nevertheless, it is not fully ... [Show full abstract] evident why students’ make their educational choices. In this paper, Swedish upper secondary school students’ perceptions of interest and self-efficacy are studied in the form of a questionnaire survey to gain deeper understanding on the choices that are made. Open-ended questions regarding subject interest, as well as questions connecting STEM-related situations with perceived emotions were included, in addition to direct questions regarding interest and self-efficacy. Differences were seen both with respect to educational orientation and to gender, which confirms previous studies. Male students were interested in subjects that are accurate, logical, and scientific, while the female students emphasized the analytical and challenging aspects, in the sense that the subjects forced them to think. Interest and future opportunities affected the choice of program, while the student’s own perceived ability seemed less important. Results with respect to emotions showed that the female students in this study felt insecure and scared in STEM-related situations to higher degree than male students did. Students on the social science program were bored and uninterested, while natural science and technology program students were more interested and confident in STEM-related scenarios. These findings help us to understand how students approach STEM situations, and how to take necessary measures to equalize these situations using a norm-critical approach.