As part of a longitudinal study of the development and implementation of a middle school engineering design curriculum, we have used an occupational values subscale of the Assessing Men and Women in Engineering (AWE) project's Engineering version of the Core Survey for Middle School-Aged Participants to measure student occupational interest in science, technology, engineering, and mathematics (STEM). According to the developers, this set of tools is intended to measure factors related to STEM careers, including occupational interests. While the AWE tools have been widely used, there have been no formal examinations of the psychometric properties of the middle school tools. Using a sample of our program participants, we examined the underlying factor structures of the occupational values subscale using exploratory and confirmatory factor analysis. We found that the AWE Work Values scale assesses two separate sets of occupational values: (1) using analytical and problem-solving skills and (2) personal satisfaction. Even though these two factors were confirmed, we conclude that there is still a need to improve reliability and more clearly define the constructs measured.