We present validity evidence for the Expectancy-Value-Cost (EVC) Scale of student motivation. Using a brief, 10-item scale, we measured middle school students' expectancy, value, and cost for their math and science classes in the Fall and Winter of the same academic year. Confirmatory factor analyses supported the three-factor structure of the EVC Scale, as well as measurement invariance across gender, academic domain, and time. Predictions of the EVC Scale's relationship with domain-specific future interest and prior achievement provide convergent and discriminant validity evidence. The practical utility of the survey is highlighted by the short administration time and the alignment between observed and latent means, indicating that practitioners can use raw scores rather than latent values. Finally, we discuss methods of how to use the EVC Scale to provide actionable information for educational practitioners, such as identifying which motivation interventions are most needed for students and if those interventions are working.