In the interest of understanding choices related to achievement, persistence, and performance that inform pursuit of careers in science, technology, engineering, and math, the current research pursued a novel approach to asking young children about their beliefs related to engineering. The Engineering-Related Activities and Skills (ERAS) items were developed to use instead of the term 'engineering' to measure children's achievement-related ability beliefs (competence) and subjective task values (importance, interest). A range of methods across three studies were implemented in the development and assessment of evidence related to the internal structure of the ERAS items across the domains of ability beliefs and subjective task values (N = 949 students). Results suggest initial evidence for the ERAS items being valid in measuring children's perceptions of engineering-related competence, importance, and interest. Theoretical and practical implications related to the factors that influence the academic and career choices in the science, technology, engineering, and math (STEM) fields, as well as future directions are outlined.