This article describes the development and validation of an Innovation Attitude Survey (IAS) composed of 16 Likert-type items selected to measure middle school students' attitudes toward innovation and leadership in the advancement of new ideas. The goal of developing the IAS was to identify desirable dispositions that may be related to future STEM careers. Data gathered from 764 middle school students from one state in the United States in 2021 were used to validate the instrument and establish the measurement properties of the instrument's scales. Factor analysis revealed three stable constructs representing a) propensity to be inventive, b) motivation or pride, and c) leadership, which were confirmed with multidimensional scaling techniques. Internal consistency reliability was found to be excellent for the total survey, very good for two of the separate scales, and acceptable for the third scale. Since the IAS was created to provide measures for a project-based STEM education program, educators may find this instrument useful for assessing pre-to-post intervention changes as well as for identifying differences in selected groups of students. Tangential findings from this instrument validation exercise indicate that the IAS can add valuable knowledge to STEM education in areas not previously assessed at the middle school level but potentially important for the pursuit of STEM careers.